{"id":6917,"date":"2024-08-13T12:28:27","date_gmt":"2024-08-13T12:28:27","guid":{"rendered":"https:\/\/www.insanelymac.com\/blog\/?p=6917"},"modified":"2024-10-23T21:13:59","modified_gmt":"2024-10-23T21:13:59","slug":"fix-corrupted-external-hard-drive-mac","status":"publish","type":"post","link":"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/","title":{"rendered":"How to Fix Corrupted External Hard Drive on a Mac"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_69_1 counter-hierarchy ez-toc-counter ez-toc-transparent ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title \" >Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 eztoc-toggle-hide-by-default' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#how_macos_and_the_drive_itself_indicate_that_external_drive_is_corrupted\" title=\"How macOS and the Drive Itself Indicate That External Drive Is Corrupted\">How macOS and the Drive Itself Indicate That External Drive Is Corrupted<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#start_with_these_5_basic_troubleshooting_steps\" title=\"Start With These 5 Basic Troubleshooting Steps\">Start With These 5 Basic Troubleshooting Steps<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#1_check_the_connections\" title=\"1. Check the Connections\">1. Check the Connections<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#2_check_drive_in_disk_utility\" title=\"2. Check Drive in Disk Utility\">2. Check Drive in Disk Utility<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#3_mount_partition_in_disk_utility\" title=\"3. Mount Partition in Disk Utility\">3. Mount Partition in Disk Utility<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#4_show_drive_in_finder\" title=\"4. Show Drive in Finder\">4. Show Drive in Finder<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#5_try_accessing_the_hard_drive_in_safe_mode\" title=\"5. Try Accessing the Hard Drive in Safe Mode\">5. Try Accessing the Hard Drive in Safe Mode<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#no_results_yet_time_for_more_advanced_methods\" title=\"No Results Yet? Time for More Advanced Methods\">No Results Yet? Time for More Advanced Methods<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#method_1_reset_smc_and_nvram\" title=\"Method 1. Reset SMC and NVRAM\">Method 1. Reset SMC and NVRAM<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#method_2_use_first_aid_for_external_hard_drive\" title=\"Method 2. Use First Aid for External Hard Drive\">Method 2. Use First Aid for External Hard Drive<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#how_to_repair_external_hard_drive_using_mac_terminal\" title=\"How to Repair External Hard Drive Using Mac Terminal\">How to Repair External Hard Drive Using Mac Terminal<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#method_1_use_fsck_command_to_repair_file_system\" title=\"Method 1. Use fsck Command To Repair File System\">Method 1. Use fsck Command To Repair File System<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#method_2_use_testdisk_to_restore_partition\" title=\"Method 2. Use TestDisk to Restore Partition\">Method 2. Use TestDisk to Restore Partition<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-14\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#if_nothing_worked_get_back_your_data_and_clean_the_slate_with_a_fresh_format\" title=\"If Nothing Worked, Get Back Your Data and Clean the Slate with a Fresh Format\">If Nothing Worked, Get Back Your Data and Clean the Slate with a Fresh Format<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-15\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#step_1_recover_data_from_a_corrupted_external_hard_drive_on_a_mac\" title=\"Step 1. Recover Data From a Corrupted External Hard Drive on a Mac\">Step 1. Recover Data From a Corrupted External Hard Drive on a Mac<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-16\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#step_2_format_external_hard_drive\" title=\"Step 2. Format External Hard Drive\">Step 2. Format External Hard Drive<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-17\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#when_to_contact_data_recovery_services\" title=\"When to Contact Data Recovery Services\">When to Contact Data Recovery Services<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-18\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#in_conclusion\" title=\"In Conclusion\">In Conclusion<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-19\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#faq\" title=\"FAQ\">FAQ<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-20\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#what_does_first_aid_do_in_disk_utility\" title=\"What does &#039;First Aid&#039; do in Disk Utility?\">What does 'First Aid' do in Disk Utility?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-21\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#can_i_fix_a_physically_damaged_external_hard_drive\" title=\"Can I fix a physically damaged external hard drive?\">Can I fix a physically damaged external hard drive?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-22\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#how_do_i_fix_a_corrupted_external_hard_drive_without_formatting_on_mac\" title=\"How do I fix a corrupted external hard drive without formatting on Mac?\">How do I fix a corrupted external hard drive without formatting on Mac?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-23\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#can_disk_utility_recover_lost_data\" title=\"Can Disk Utility recover lost data?\">Can Disk Utility recover lost data?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-24\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/#what_are_the_best_third-party_tools_for_external_hard_drive_repair_on_mac\" title=\"What are the best third-party tools for external hard drive repair on Mac?\">What are the best third-party tools for external hard drive repair on Mac?<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<p>A corrupted external hard drive poses a serious problem for Mac users, often leading to error messages, blocked file access, or sluggish performance. We\u2019ll walk you through different ways to fix a corrupted external hard drive on your Mac, using tools and features already built into macOS, as well as third-party apps. These steps should help you recover your data and get your external hard drive back to normal.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"how_macos_and_the_drive_itself_indicate_that_external_drive_is_corrupted\"><\/span>How macOS and the Drive Itself Indicate That External Drive Is Corrupted<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>When an external drive becomes corrupted, both macOS and the drive will often give you clear signs that something is wrong, such as:<\/p>\n<ul>\n<li>\ud83d\udeab <strong>Error messages.<\/strong>\u00a0Frequent alerts such as &#8220;Disk not readable&#8221; or &#8220;Error writing to disk&#8221; may appear when you attempt to access or write data to the drive.<\/li>\n<li>\ud83d\udc0c <strong>Slow performance.<\/strong>\u00a0A clear drop in data transfer speeds or long delays, when you try to open files, can signal deeper hard drive problems.<\/li>\n<li>\u2753 <strong>Missing files.<\/strong>\u00a0Files that suddenly disappear or become inaccessible, even though they were not manually deleted, can signal corruption within the drive.<\/li>\n<li>\ud83d\udd09 <strong>Strange noises.<\/strong>\u00a0Unusual sounds like clicking or grinding from the drive often indicate physical damage, which can lead to data corruption.<\/li>\n<li>\ud83d\uddc3\ufe0f <strong>Inconsistent file listings.<\/strong>\u00a0Changes in file or folder visibility without any user action suggest errors in the drive&#8217;s directory structures.<\/li>\n<li>\ud83d\udd0c <strong>The drive disconnects\/fails to mount<\/strong>. A corrupted external drive may randomly disconnect from your Mac without warning. You may also encounter situations where the drive doesn&#8217;t mount at all when you plug it in.<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"start_with_these_5_basic_troubleshooting_steps\"><\/span>Start With These 5 Basic Troubleshooting Steps<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>If your external drive shows any of these signs, before jumping into advanced fixes, try some basic troubleshooting steps that can often resolve the issue quickly. Start with these five simple checks:<\/p>\n<h3><span class=\"ez-toc-section\" id=\"1_check_the_connections\"><\/span>1. Check the Connections<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>First of all, you need to check the connections. Quite often, a bad connection between your external hard drive and your Mac might look like the drive is corrupted when in reality it\u2019s just a loose or faulty cable. <strong>Here\u2019s what you can try:<\/strong><\/p>\n<ul>\n<li>Check that the USB or Thunderbolt cable connecting your external hard drive to your Mac is secure. Sometimes, simply reseating the cable can resolve connectivity issues.<\/li>\n<li>Switch the cable to a different port on your Mac. A faulty port can cause the drive to malfunction, so testing multiple ports can help isolate the issue.<\/li>\n<li>Cables can degrade or become faulty over time. Try a different cable to determine if the issue lies with the original one.<\/li>\n<li>Connect your external hard drive to another Mac to avoid system-specific issues. This step can help determine whether the problem is with the drive itself or your computer&#8217;s configuration.<\/li>\n<\/ul>\n<div class=\"frame_bg frame_bg--default\"><div class=\"frame_bg--title\"><\/div>\ud83d\udccc <strong>Note<\/strong>. It\u2019s best to connect external drives directly to your Mac or MacBook, without using hubs. Hubs can sometimes cause connection problems or limit power, which might affect how the drive works.<\/div>\n<h3><span class=\"ez-toc-section\" id=\"2_check_drive_in_disk_utility\"><\/span>2. Check Drive in Disk Utility<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The next step is to check your external drive in Disk Utility. This built-in macOS tool is designed to manage and diagnose issues with storage devices. We can use it to verify whether your external hard drive is recognized by your Mac and displayed with the correct size. This can be an initial indicator of the drive\u2019s health and a preliminary step in troubleshooting drive issues. <strong>Here\u2019s how you can utilize Disk Utility to check your external hard drive:<\/strong><\/p>\n<ol>\n<li>You can Access Disk Utility by navigating to the Utilities folder within your Applications folder or simply using Spotlight search to find and open Disk Utility.<img fetchpriority=\"high\" class=\"border-gray aligncenter wp-image-6930 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/open-disk-utility.jpg\" alt=\"Open Disk Utility\" width=\"2105\" height=\"1103\" \/><\/li>\n<li>In Disk Utility, go to the &#8220;View&#8221; menu and select &#8220;Show All Devices.&#8221; This provides that both drives and their corresponding partitions are visible in the sidebar.<img class=\"border-gray aligncenter wp-image-6939 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/show-all-devices-disk-utility.jpg\" alt=\"Show all devices in Disk Utility\" width=\"1556\" height=\"561\" \/><\/li>\n<li>Select the external hard drive you wish to check from the sidebar in Disk Utility. This step confirms whether your Mac recognizes the drive.<\/li>\n<li>With the drive selected, examine the information displayed at the bottom of Disk Utility or click on the &#8220;Info&#8221; button for more detailed data. Check that the capacity and used space are accurately reported, which can confirm the drive&#8217;s proper functionality. You can also use <a href=\"\/blog\/best-apps-to-test-mac-hard-drive\/\">specialized programs to check the drive&#8217;s health<\/a>.<img class=\"border-gray aligncenter wp-image-6924 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/disk-info-disk-utility.jpg\" alt=\"Info about drive in Disk Utility\" width=\"2105\" height=\"1103\" \/><\/li>\n<li>If the drive&#8217;s information appears correct and the drive is recognized, it&#8217;s a positive sign of its operational status. However, if the drive does not appear or shows incorrect data, it may indicate physical issues with the drive or connection.<\/li>\n<\/ol>\n<p>If Disk Utility doesn\u2019t show your external drive at all, it could point to more serious problems, likely physical damage, that no DIY method can fix. In such cases, you may need to consider professional data recovery services.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"3_mount_partition_in_disk_utility\"><\/span>3. Mount Partition in Disk Utility<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>If your external hard drive is recognized by Disk Utility but isn\u2019t mounting automatically, you can try to mount it manually. This action can help restore access to your data if the drive itself doesn\u2019t have severe physical or file system damage. <strong>Here\u2019s how to manually mount a partition using Disk Utility:<\/strong><\/p>\n<ol>\n<li>In Disk Utility, find your external hard drive listed under the external section in the sidebar. Click on it to select it.<\/li>\n<li>When the drive is selected, the partitions appear beneath the drive name. Select the partition you want to mount.<\/li>\n<li>Click the &#8220;Mount&#8221; button at the top of the Disk Utility window or right-click on the partition and select &#8220;Mount&#8221;. If the mount button is greyed out, this could indicate that the system cannot mount the partition due to underlying issues.<img loading=\"lazy\" class=\"border-gray aligncenter wp-image-6929 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/mount-partition-in-disk-utility.jpg\" alt=\"Mount partition in Disk Utility\" width=\"2105\" height=\"1103\" \/><\/li>\n<li>After clicking mount, watch the partition appear on your Desktop or in the Finder sidebar. This indicates that the partition is now accessible.<\/li>\n<\/ol>\n<p>If the partition doesn\u2019t mount or Disk Utility shows errors during the process, you might need to take extra steps to repair the external hard drive on your Mac and fix any file system issues.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"4_show_drive_in_finder\"><\/span>4. Show Drive in Finder<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Sometimes, even if your external hard drive is working properly and mounted in Disk Utility, it may not show up in Finder or on your Desktop due to display settings. <strong>Here\u2019s how to configure Finder to show your external hard drive:<\/strong><\/p>\n<ol>\n<li>Click on the Finder icon in your Dock to open a new Finder window.<\/li>\n<li>In the Finder menu at the top of the screen, select \u2018Settings\u2019 or use the shortcut <strong>Command<\/strong> + &#8220;<strong>,<\/strong>&#8220;.<img loading=\"lazy\" class=\"border-gray aligncenter wp-image-6931 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/open-finder-settings.jpg\" alt=\"Open finder settings\" width=\"1424\" height=\"611\" \/><\/li>\n<li>Click on the \u2018Sidebar\u2019 tab within the Finder Preferences window. Here, you can customize which items appear in the sidebar.<\/li>\n<li>Under the \u2018Locations\u2019 section, use the checkbox \u2018External disks\u2019 to make all connected external hard drives visible in the Finder sidebar.<img loading=\"lazy\" class=\"border-gray aligncenter wp-image-6940 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/show-external-drives-in-sidebar.jpg\" alt=\"Show external disks in sidebar Finder\" width=\"1828\" height=\"846\" \/><\/li>\n<li>Navigate to the \u2018General\u2019 tab in the Finder Preferences. Make sure the \u2018External disks\u2019 option is checked under the \u2018Show these items on the desktop\u2019 section. This means that external hard drives appear on your Desktop as well.<img loading=\"lazy\" class=\"border-gray aligncenter wp-image-6941 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/show-external-drives-on-desktop.jpg\" alt=\"Show external disks on desktop\" width=\"1828\" height=\"846\" \/><\/li>\n<li>Close the Preferences window to save your settings. Your external hard drive should now appear both in the Finder sidebar and on the Desktop.<\/li>\n<\/ol>\n<div class=\"frame_bg frame_bg--primary\"><div class=\"frame_bg--title\"><\/div>\ud83d\udc49 <strong>Tip<\/strong>. If your external drive still doesn\u2019t appear after adjusting Finder preferences, restart your Mac. A quick reboot often refreshes the system and helps the drive show up as expected.<\/div>\n<h3><span class=\"ez-toc-section\" id=\"5_try_accessing_the_hard_drive_in_safe_mode\"><\/span>5. Try Accessing the Hard Drive in Safe Mode<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>In some rare cases, software conflicts or third-party drivers might prevent your external hard drive from working properly. To rule this out, you can try accessing the drive in <a href=\"https:\/\/support.apple.com\/en-gb\/guide\/mac-help\/mh21245\/mac\" target=\"_blank\" rel=\"noopener\">Safe Mode<\/a>. Safe Mode limits the Mac to its basic functions, which prevents third-party software from interfering with the operating system and connected devices. <strong>Here\u2019s how to access your hard drive in Safe Mode:<\/strong><\/p>\n<ol>\n<li>Turn on your Mac and immediately press and hold the <strong>Shift<\/strong> key. Release the <strong>Shift<\/strong>\u00a0key when you see the login window. Note that startup is likely to take longer than usual.<\/li>\n<li>Once your Mac starts in Safe Mode, connect your external hard drive. Check if the drive is recognized and whether you can access the files In Finder.<\/li>\n<li>If the drive is accessible in Safe Mode, you can use this opportunity to back up your data or transfer important files from the external drive to your Mac.<\/li>\n<li>After that, restart your Mac without holding any keys to exit Safe Mode and return to normal operation.<\/li>\n<\/ol>\n<div class=\"frame_bg frame_bg--default\"><div class=\"frame_bg--title\"><\/div>\ud83d\udccc <strong>Note.<\/strong> Single User Mode for deeper diagnostics only works on Intel-based Macs.<\/div>\n<p>If you can access your hard drive in Safe Mode, it\u2019s likely that non-essential software or drivers are to blame. After you restart macOS, check any apps or drivers you\u2019ve recently installed. Try to uninstall them one by one to figure out which one might be causing the issue.<\/p>\n<p>However, if problems persist even in Safe Mode, it may indicate more severe hardware issues or file system corruption that requires further investigation.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"no_results_yet_time_for_more_advanced_methods\"><\/span>No Results Yet? Time for More Advanced Methods<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>If the basic fixes haven\u2019t done the trick, it\u2019s time to try more advanced solutions. These methods tackle deeper issues with your external hard drive, whether it\u2019s severe file system corruption or hardware problems on your Mac.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"method_1_reset_smc_and_nvram\"><\/span>Method 1. Reset SMC and NVRAM<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Resetting the System Management Controller (SMC) and Non-Volatile Random-Access Memory (NVRAM) on your Mac can help resolve various hardware-related issues. These resets can fix corrupted hard drives on Mac caused by problems related to power management, battery behavior, etc. <strong>Here&#8217;s how to properly reset the SMC and NVRAM:<\/strong><\/p>\n<p><b>Reset the SMC (for MacBooks with non-removable batteries and other Macs)<\/b><\/p>\n<ol>\n<li>Shut down your Mac.<\/li>\n<li>For MacBooks, hold down <strong>Shift<\/strong> + <strong>Control<\/strong> + <strong>Option<\/strong> on the left side of the built-in keyboard and press the power button at the same time. Hold these keys and the power button for 10 seconds.<\/li>\n<li>For desktop Macs, unplug the power cord, wait 15 seconds, plug it back in, and wait another 5 seconds before turning it back on.<\/li>\n<li>Release all keys and the power button at the same time.<\/li>\n<li>Turn on your Mac.<\/li>\n<\/ol>\n<p><b>Reset the NVRAM (only for Intel-based Macs)<\/b><\/p>\n<ol>\n<li>Turn off your Mac.<\/li>\n<li>Turn on your Mac and immediately press and hold <strong>Option<\/strong> + <strong>Command<\/strong> + <strong>P<\/strong> + <strong>R.<\/strong><\/li>\n<li>Hold these keys for about 20 seconds. On some Macs, the startup sound might play a second time, or the Apple logo might appear and disappear twice.<\/li>\n<li>Release the keys after the second startup sound or the second appearance of the Apple logo.<\/li>\n<\/ol>\n<div class=\"frame_bg frame_bg--success\"><div class=\"frame_bg--title\"><\/div>\ud83d\udccc <strong>Note<\/strong>. For Macs with <a href=\"https:\/\/support.apple.com\/en-us\/116943\" target=\"_blank\" rel=\"noopener\">Apple silicon<\/a>, SMC functions are built into the M chip. There\u2019s no separate SMC reset, so the closest equivalent is to simply restart your computer or turn it off and back on again, similar to NVRAM.<\/div>\n<p>After performing these resets, reconnect your external hard drive and check if the issues have been resolved. These steps can sometimes rectify seemingly stubborn hardware-related problems and are particularly useful if your Mac fails to recognize an external hard drive or if you encounter persistent issues after trying previous fixes.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"method_2_use_first_aid_for_external_hard_drive\"><\/span>Method 2. Use First Aid for External Hard Drive<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>We\u2019ve already talked about using Disk Utility to check your external hard drive, but now it\u2019s time to take it a step further with <a href=\"https:\/\/support.apple.com\/en-us\/102611\" target=\"_blank\" rel=\"noopener\">First Aid<\/a>. Disk Utility\u2019s First Aid checks for various types of file system errors and attempts to correct them, which can resolve many common problems with corrupted hard drives. <strong>Here\u2019s how to use First Aid to repair an external hard drive on a Mac:<\/strong><\/p>\n<ol>\n<li>Open Disk Utility.<\/li>\n<li>In the Disk Utility sidebar, locate and select your external hard drive.<\/li>\n<li>With the drive selected, click on the &#8220;First Aid&#8221; button located at the top of the Disk Utility window. Confirm that you want to run First Aid by clicking &#8220;Run&#8221; in the prompt that appears.<img loading=\"lazy\" class=\"border-gray aligncenter wp-image-6934 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/run-first-aid.jpg\" alt=\"Run first aid in Disk Utility\" width=\"2105\" height=\"1103\" \/><\/li>\n<li>Disk Utility will begin checking the drive for errors and attempt to repair them. Keep an eye on the progress bar and any messages that appear during this process.<\/li>\n<li>Once First Aid is complete, review the final report. Disk Utility will provide a summary of any repairs made or notify you if the drive cannot be repaired.<img loading=\"lazy\" class=\"border-gray aligncenter wp-image-6926 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/first-aid-results.jpg\" alt=\"First aid report\" width=\"2105\" height=\"1103\" \/><\/li>\n<li>If First Aid reports that repairs were successful, it\u2019s advisable to restart your Mac and recheck the drive&#8217;s functionality. If the drive still shows signs of issues or if First Aid cannot repair it, further troubleshooting may be required.<\/li>\n<\/ol>\n<p>First Aid in Disk Utility can often resolve minor file system errors and restore the functionality of your external hard drive. However, if this method does not fix the problem, more severe issues may be involved, requiring advanced recovery techniques or professional assistance.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"how_to_repair_external_hard_drive_using_mac_terminal\"><\/span>How to Repair External Hard Drive Using Mac Terminal<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>If the standard methods haven\u2019t worked, you can use Terminal for a more advanced way to repair your external hard drive. There are some capable built-in and third-party tools, like <a href=\"https:\/\/appleinsider.com\/inside\/macos\/tips\/how-to-use-fsck-to-check-and-repair-macos-disks\" target=\"_blank\" rel=\"noopener\">fsck<\/a> and <a href=\"https:\/\/www.cgsecurity.org\/wiki\/TestDisk\" target=\"_blank\" rel=\"noopener\">TestDisk<\/a>, that can only be run through Terminal. This makes them less popular with users, but they\u2019re not as complicated as they may seem. We\u2019ll walk you through the detailed process.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"method_1_use_fsck_command_to_repair_file_system\"><\/span>Method 1. Use fsck Command To Repair File System<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The File System Check (fsck) command is a powerful tool available in macOS\u2019s Terminal that can help diagnose and repair file system issues on your external hard drive. <strong>Here\u2019s a step-by-step guide on how to use the fsck command to repair an external hard drive using a Mac terminal:<\/strong><\/p>\n<ol>\n<li>Open Terminal from your Applications folder or Utilities subfolder, or use Spotlight to search and launch it directly.<\/li>\n<li>Enter the appropriate fsck command <strong>sudo fsck_hfs -fy<\/strong> (for HFS formatted drives) or <strong>sudo fsck_apfs -y<\/strong> (for APFS formatted drives).<\/li>\n<li>Monitor the output in Terminal as fsck processes the file system. It will report any corrections it makes or notify you if no issues are found.<img loading=\"lazy\" class=\"border-gray aligncenter wp-image-6935 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/run-fsck-command.jpg\" alt=\"Run fsck commandr in terminal\" width=\"1576\" height=\"895\" \/><\/li>\n<li>Once the fsck process completes, restart your Mac, applying any changes made during the repair process.<\/li>\n<\/ol>\n<div class=\"frame_bg frame_bg--default\"><div class=\"frame_bg--title\"><\/div>\ud83d\udc49 <strong>Tip<\/strong>. It can be a good idea to run fsck command a few times, especially if it fixes something the first time around. Running it again makes sure everything is fully resolved and the file system is in good shape.<\/div>\n<h3><span class=\"ez-toc-section\" id=\"method_2_use_testdisk_to_restore_partition\"><\/span>Method 2. Use TestDisk to Restore Partition<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><a href=\"https:\/\/www.cgsecurity.org\/wiki\/TestDisk\" target=\"_blank\" rel=\"noopener\">TestDisk<\/a> is an advanced, open-source software tool designed to recover lost partitions and make non-booting disks bootable again. This tool can be incredibly useful when dealing with severe corruption or accidental deletion of partitions on your external hard drive. <strong>Here&#8217;s how to use TestDisk to attempt restoration of your drive&#8217;s partitions:<\/strong><\/p>\n<ol>\n<li>If you don\u2019t already have <a href=\"https:\/\/brew.sh\/\" target=\"_blank\" rel=\"noopener\">Homebrew<\/a> installed, open Terminal and enter the following command: <strong>\/bin\/bash -c &#8220;$(curl -fsSL https:\/\/raw.githubusercontent.com\/Homebrew\/install\/HEAD\/install.sh)&#8221;<\/strong><\/li>\n<li>After installing Homebrew, install TestDisk by typing <strong>brew install testdisk<\/strong>\u00a0in Terminal and pressing Enter.<\/li>\n<li>Once the installation is complete, type <strong>sudo testdisk<\/strong>\u00a0in Terminal and press Enter to run the program with administrative privileges. You may need to enter your administrator password.<\/li>\n<li>Follow the on-screen instructions to select your external hard drive from the list of available drives.<img loading=\"lazy\" class=\"border-gray aligncenter wp-image-6938 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/select-drive-in-testdisk.jpg\" alt=\"Select drive in testdisk\" width=\"1576\" height=\"895\" \/><\/li>\n<li>Choose the \u2018Analyse\u2019 option to search for lost partitions. TestDisk will scan your drive and attempt to find any deleted or damaged partitions.<img loading=\"lazy\" class=\"border-gray aligncenter wp-image-6921 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/analyse-drive-in-testdisk.jpg\" alt=\"Analyse drive in testdisk\" width=\"1576\" height=\"895\" \/><\/li>\n<li>If TestDisk finds partitions that can be recovered, it will display them. Select the partitions you wish to recover and follow the prompts to write the recovered partition structure back to the disk. Exercise caution during this step to avoid further data loss.<img loading=\"lazy\" class=\"border-gray aligncenter wp-image-6927 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/found-partitions-testdisk.jpg\" alt=\"Found partition in testdisk\" width=\"1576\" height=\"895\" \/><\/li>\n<li>After completing the recovery process, exit TestDisk and reboot your Mac to make sure all changes take effect.<\/li>\n<\/ol>\n<div class=\"frame_bg frame_bg--primary\"><div class=\"frame_bg--title\"><\/div>\ud83d\udccc <strong>Note<\/strong>. Be careful when you select the drive in TestDisk. Pay attention to the disk size and compare it with what is shown in Disk Utility. If you select the wrong drive, you could accidentally overwrite or delete important data, so double-check before moving forward.<\/div>\n<h2><span class=\"ez-toc-section\" id=\"if_nothing_worked_get_back_your_data_and_clean_the_slate_with_a_fresh_format\"><\/span>If Nothing Worked, Get Back Your Data and Clean the Slate with a Fresh Format<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Now, if at this point your external hard drive is still giving you problems, it\u2019s likely time to recover your data and reformat the drive. Reformatting usually fixes all non-physical issues, such as corrupted file systems, partition problems, and allocation errors. This process resets the drive as if it were brand new. It clears out all data structures, which is why it\u2019s so effective at resolving software-related issues.<\/p>\n<p>Just remember, this process erases everything on the drive. If you want to keep your data, you\u2019ll need to handle it in two steps: first, recover your files, then reformat the drive.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"step_1_recover_data_from_a_corrupted_external_hard_drive_on_a_mac\"><\/span>Step 1. Recover Data From a Corrupted External Hard Drive on a Mac<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>macOS doesn\u2019t come with any built-in data recovery tools, so you\u2019ll need to rely on third-party software to recover data from a corrupted external hard drive. We\u2019ve <a href=\"https:\/\/www.insanelymac.com\/blog\/best-mac-data-recovery-software\/\">reviewed and tested many data recovery options<\/a>, and one of the best for this task is <a href=\"https:\/\/www.cleverfiles.com\/\" target=\"_blank\" rel=\"noopener\">Disk Drill<\/a>, a tool that\u2019s been around for more than a decade. <strong>Here\u2019s why we recommend it:<\/strong><\/p>\n<ul>\n<li>Disk Drill works great with a variety of storage devices, including internal drives, memory cards, and of course, external hard drives.<\/li>\n<li>Disk Drill can recover data from drives that don\u2019t show up in Finder but are visible in Disk Utility, even if the drive doesn\u2019t mount properly.<\/li>\n<li>Can recover data from a wide range of file systems commonly found on external hard drives, including HFS+, APFS, FAT32, exFAT, and even NTFS, which isn\u2019t natively supported by macOS.<\/li>\n<li>Can recover data from drives with severely damaged file systems or none at all thanks to its Signature Scan (It identifies file types based on their unique binary patterns, or \u201csignatures,\u201d rather than relying on the file system itself.)<\/li>\n<li>Can recover deleted\/lost data from hard drives.<\/li>\n<li>Disk Drill also offers extra features like disk health monitoring and data protection tools.<\/li>\n<\/ul>\n<p><strong>Here\u2019s a step-by-step guide on how to use Disk Drill to recover data from a corrupted external hard drive on a Mac:<\/strong><\/p>\n<div class=\"frame_bg frame_bg--default\"><div class=\"frame_bg--title\"><\/div>\ud83d\udccc <strong>Note.<\/strong> If your disk shows signs of severe damage, use Disk Drill\u2019s \u201cByte-to-Byte Backup\u201d feature to create an exact copy of the drive. This way, you can scan and recover files from the backup instead of the external drive itself, which protects the original drive from further stress. To make a backup, find Byte-to-Byte Backup in the main menu, select your drive, and click on the &#8220;Create Backup&#8221; button. Just make sure you have a target disk with free space that exceeds the total size of the problematic disk.<img loading=\"lazy\" class=\"border-gray aligncenter wp-image-6923 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/disk-drill-backup-option-scaled.jpg\" alt=\"Disk drill backup option\" width=\"2560\" height=\"1538\" \/><\/div>\n<ol>\n<li>Visit the CleverFiles website to <a href=\"https:\/\/www.cleverfiles.com\/download.html\" target=\"_blank\" rel=\"noopener\">download<\/a> the latest version of Disk Drill for macOS. Install it by dragging the application icon to your Applications folder.<img loading=\"lazy\" class=\"border-gray aligncenter wp-image-6775 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/07\/download-and-install-disk-drill.jpg\" alt=\"Install Disk Drill for macos\" width=\"1504\" height=\"1076\" \/><\/li>\n<li>Open Disk Drill from your Applications folder. You may need to allow the application permissions to access your disk drives in your system\u2019s security settings.<\/li>\n<li>Connect your external hard drive to your Mac. If the drive is detectable, Disk Drill should list it under the available drives.<\/li>\n<li>Find your external hard drive and select it. If you previously created a Byte-to-byte Backup of the drive, you can click on &#8220;Attach disk image&#8221; instead and select the backup. Once selected, click \u201cSearch for lost data\u201d to begin the recovery process.<img loading=\"lazy\" class=\"border-gray aligncenter wp-image-6937 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/select-corrupted-drive-in-disk-drill-scaled.jpg\" alt=\"Select corrupt hard drive in Disk Drill\" width=\"2560\" height=\"1538\" \/><\/li>\n<li>Even before the scan is complete, you can click \u201cRecover all\u201d to immediately recover all files found so far, or click \u201cReview found items\u201d to browse through the files already detected. In the list of recoverable files, you\u2019ll notice they are grouped into categories such as:\n<ul>\n<li><strong>Existing files<\/strong>: These are files that are still present on the drive but might not be accessible through normal means.<\/li>\n<li><strong>Deleted or lost<\/strong>: These are files that were deleted\/lost due to corruption or other issues.<\/li>\n<li><strong>Reconstructed<\/strong>: These are files that Disk Drill was able to piece back together from fragments using its recovery algorithms, often from severely damaged drives.<\/li>\n<\/ul>\n<p>You can browse these groups to locate the files you need to recover.<img loading=\"lazy\" class=\"border-gray aligncenter wp-image-6932 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/preview-files-in-disk-drill-scaled.jpg\" alt=\"Review found data in Disk Drill results\" width=\"2560\" height=\"1538\" \/><\/li>\n<li>Mark the files or folders you want to recover and click the &#8220;Recover&#8221; button. To avoid potential data overwriting, it\u2019s advisable to recover the files to a different drive than the one recovered from.<img loading=\"lazy\" class=\"border-gray aligncenter wp-image-6933 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/recovery-location-disk-drill-scaled.jpg\" alt=\"Select save location in Disk Drill\" width=\"2560\" height=\"1538\" \/><\/li>\n<li>Click the &#8220;Next&#8221; button to save the files to your chosen location.<\/li>\n<\/ol>\n<h3><span class=\"ez-toc-section\" id=\"step_2_format_external_hard_drive\"><\/span>Step 2. Format External Hard Drive<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Once you&#8217;ve successfully recovered your data, it\u2019s time to reformat the external hard drive to fix any file system corruption or errors. To reformat the drive, we will once again use Disk Utility. <strong>Here\u2019s how to format your external hard drive on a Mac:<\/strong><\/p>\n<ol>\n<li>Open Disk Utility.<\/li>\n<li>Locate and select your external hard drive from the list of available drives.<\/li>\n<li>Click the &#8220;Erase&#8221; button at the top of the Disk Utility window. You will be prompted to choose a file system format and a drive name.<\/li>\n<li>Select a file system format suitable for your needs. Depending on your macOS version, choose APFS or Mac OS Extended (Journaled) for Mac compatibility, or choose exFAT for maximum compatibility with other OS.<\/li>\n<li>Choose a name for your drive, and click &#8220;Erase&#8221; to begin formatting. Monitor the progress in Disk Utility.<img loading=\"lazy\" class=\"border-gray aligncenter wp-image-6925 size-full\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/08\/erase-drive-disk-utility.jpg\" alt=\"Erase drive in Disk Utility\" width=\"2105\" height=\"1103\" \/><\/li>\n<li>Once the formatting is complete, Disk Utility will display a success message. Close Disk Utility and eject the drive properly before disconnecting it.<\/li>\n<li>Reconnect your drive to verify that it appears correctly in Finder and is ready for use.<\/li>\n<\/ol>\n<p>Formatting your external hard drive effectively resets it, providing a clean slate for new data. After formatting, the drive will be ready for use, and you can transfer your recovered data back onto it.<\/p>\n<div class=\"frame_bg frame_bg--success\"><div class=\"frame_bg--title\"><\/div>\ud83d\udccc <strong>Note<\/strong>. When formatting your external hard drive, you&#8217;ll also see an option for Scheme. If you\u2019re unsure whether your drive needs a GUID Partition Map or Master Boot Record, it\u2019s best to choose GUID for better compatibility with macOS, especially on newer Macs. Master Boot Record (MBR) is typically used for older Windows systems or drives that will only be used with Windows. For dual compatibility between macOS and Windows, GUID Partition Map is recommended.<\/div>\n<h2><span class=\"ez-toc-section\" id=\"when_to_contact_data_recovery_services\"><\/span>When to Contact Data Recovery Services<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>If you\u2019ve tried all the troubleshooting methods and data recovery tools available, but your external hard drive is still inaccessible or not functioning properly, it may be time to consider professional data recovery services.<\/p>\n<p>Professional data recovery services are a good option when faced with a corrupted external hard drive that DIY methods cannot restore. These services are equipped to handle complex recovery scenarios beyond the reach of standard software solutions. This includes drives with severe physical damage, such as those affected by water or impact, and those suffering from serious mechanical failures like head crashes or motor issues.<\/p>\n<p>Professional data recovery firms use advanced tools and technologies in controlled cleanroom environments to open and repair physically damaged drives without causing further harm. While they can be expensive, the cost is often justified by the high success rates and the ability to recover data that would otherwise be permanently lost.<\/p>\n<div class=\"frame_bg frame_bg--primary\"><div class=\"frame_bg--title\"><\/div>\ud83d\udccc <strong>Note<\/strong>. Many services operate on a &#8220;no data, no fee&#8221; basis, which means you only pay if they successfully recover your data.<\/div>\n<h2><span class=\"ez-toc-section\" id=\"in_conclusion\"><\/span>In Conclusion<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>In most cases, the DIY methods we covered in this article are enough to fix a corrupted hard drive using a Mac. Usually, these issues come from logical problems that you can fix with macOS utilities or third-party apps like TestDisk or Disk Drill.<\/p>\n<p>To avoid these issues again, it\u2019s important to treat your external drive with care. Always use the <strong>safely eject<\/strong> option before you unplug your drive to prevent data corruption. Plus, consider a <strong>carrying case<\/strong> for your external hard drive to protect it from physical damage while you transport it.<\/p>\n<div class=\"frame_bg frame_bg--default\"><div class=\"frame_bg--title\"><\/div>\ud83d\udc49 <strong>Tip<\/strong>. All modern hard drives have S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology) built in. This feature tracks your drive&#8217;s health by checking factors like temperature, read\/write errors, and overall performance.<\/p>\n<p><img loading=\"lazy\" class=\"size-full wp-image-8240\" src=\"\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2024\/10\/disk-drill-smart-light-scaled.jpg\" alt=\"S.M.A.R.T. monitoring in Disk Drill\" width=\"2560\" height=\"1533\" \/><\/p>\n<p>You can activate <a href=\"https:\/\/www.cleverfiles.com\/help\/monitor-smart-status-disk-health\/\" target=\"_blank\" rel=\"noopener\">S.M.A.R.T. monitoring in Disk Drill<\/a>, which will alert you if it detects any problems with your drives. Once activated, a new icon will display the drive&#8217;s temperature and health status, so you can easily keep tabs on your drive&#8217;s condition.<\/p>\n<\/div>\n<section itemscope=\"\" itemtype=\"https:\/\/schema.org\/FAQPage\"><div class=\"panel-group sc_accordion_faq\" id=\"accordion\" role=\"tablist\" aria-multiselectable=\"true\"><h2 class=\"sc_accordion_faq--title\"><span class=\"ez-toc-section\" id=\"faq\"><\/span>FAQ<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<div class=\"panel panel-default\" itemprop=\"mainEntity\" itemscope=\"\" itemtype=\"http:\/\/schema.org\/Question\">\r\n    <div class=\"panel-heading\" role=\"tab\" id=\"heading1\" aria-selected=\"true\">\r\n        <h3 class=\"panel-title\" itemprop=\"name\"><span class=\"ez-toc-section\" id=\"what_does_first_aid_do_in_disk_utility\"><\/span>\r\n            <a role=\"button\" data-toggle=\"collapse\" href=\"#collapse1\" aria-expanded=\"true\" aria-controls=\"collapse1\">\r\n                What does 'First Aid' do in Disk Utility?\r\n                <i class=\"fas fa-plus\"><\/i>\r\n            <\/a>\r\n        <span class=\"ez-toc-section-end\"><\/span><\/h3>\r\n    <\/div>\r\n    <div id=\"collapse1\" class=\"panel-collapse collapse in\" role=\"tabpanel\" aria-labelledby=\"heading1\">\r\n        <div class=\"panel-body\" itemprop=\"acceptedAnswer\" itemscope=\"\" itemtype=\"http:\/\/schema.org\/Answer\">\r\n            <div itemprop=\"text\">\r\n                \u201cFirst Aid\u201d in Disk Utility is a tool designed to check and repair file system errors on your drive. When you run First Aid, it assesses the drive for errors such as corrupted files or inconsistencies and attempts to fix these issues to improve the drive\u2019s functionality and access to stored data.\r\n            <\/div>\r\n        <\/div>\r\n    <\/div>\r\n<\/div>\n<div class=\"panel panel-default\" itemprop=\"mainEntity\" itemscope=\"\" itemtype=\"http:\/\/schema.org\/Question\">\r\n    <div class=\"panel-heading\" role=\"tab\" id=\"heading2\" aria-selected=\"true\">\r\n        <h3 class=\"panel-title\" itemprop=\"name\"><span class=\"ez-toc-section\" id=\"can_i_fix_a_physically_damaged_external_hard_drive\"><\/span>\r\n            <a role=\"button\" data-toggle=\"collapse\" href=\"#collapse2\" aria-expanded=\"true\" aria-controls=\"collapse2\">\r\n                Can I fix a physically damaged external hard drive?\r\n                <i class=\"fas fa-plus\"><\/i>\r\n            <\/a>\r\n        <span class=\"ez-toc-section-end\"><\/span><\/h3>\r\n    <\/div>\r\n    <div id=\"collapse2\" class=\"panel-collapse collapse in\" role=\"tabpanel\" aria-labelledby=\"heading2\">\r\n        <div class=\"panel-body\" itemprop=\"acceptedAnswer\" itemscope=\"\" itemtype=\"http:\/\/schema.org\/Answer\">\r\n            <div itemprop=\"text\">\r\n                Fixing a physically damaged external hard drive depends on the extent of the damage. Minor issues like loose connections can sometimes be repaired at home. However, severe physical damage typically requires professional services, as they have the necessary tools and environment to repair the drive without causing further damage.\r\n            <\/div>\r\n        <\/div>\r\n    <\/div>\r\n<\/div>\n<div class=\"panel panel-default\" itemprop=\"mainEntity\" itemscope=\"\" itemtype=\"http:\/\/schema.org\/Question\">\r\n    <div class=\"panel-heading\" role=\"tab\" id=\"heading3\" aria-selected=\"true\">\r\n        <h3 class=\"panel-title\" itemprop=\"name\"><span class=\"ez-toc-section\" id=\"how_do_i_fix_a_corrupted_external_hard_drive_without_formatting_on_mac\"><\/span>\r\n            <a role=\"button\" data-toggle=\"collapse\" href=\"#collapse3\" aria-expanded=\"true\" aria-controls=\"collapse3\">\r\n                How do I fix a corrupted external hard drive without formatting on Mac?\r\n                <i class=\"fas fa-plus\"><\/i>\r\n            <\/a>\r\n        <span class=\"ez-toc-section-end\"><\/span><\/h3>\r\n    <\/div>\r\n    <div id=\"collapse3\" class=\"panel-collapse collapse in\" role=\"tabpanel\" aria-labelledby=\"heading3\">\r\n        <div class=\"panel-body\" itemprop=\"acceptedAnswer\" itemscope=\"\" itemtype=\"http:\/\/schema.org\/Answer\">\r\n            <div itemprop=\"text\">\r\n                To fix a corrupted external hard drive without formatting on a Mac, you can start with Disk Utility to run First Aid, which checks for errors and attempts repairs. If the problems are caused by lost partitions, consider the TestDisk app for recovery. You can also utilize Terminal commands like fsck to repair the file system. If these methods don\u2019t resolve the issue, you can retrieve your data with data recovery software like Disk Drill. Alternatively, if you don\u2019t want to risk it with DIY methods, there are professional data recovery services that can handle complex issues safely.\r\n            <\/div>\r\n        <\/div>\r\n    <\/div>\r\n<\/div>\n<div class=\"panel panel-default\" itemprop=\"mainEntity\" itemscope=\"\" itemtype=\"http:\/\/schema.org\/Question\">\r\n    <div class=\"panel-heading\" role=\"tab\" id=\"heading4\" aria-selected=\"true\">\r\n        <h3 class=\"panel-title\" itemprop=\"name\"><span class=\"ez-toc-section\" id=\"can_disk_utility_recover_lost_data\"><\/span>\r\n            <a role=\"button\" data-toggle=\"collapse\" href=\"#collapse4\" aria-expanded=\"true\" aria-controls=\"collapse4\">\r\n                Can Disk Utility recover lost data?\r\n                <i class=\"fas fa-plus\"><\/i>\r\n            <\/a>\r\n        <span class=\"ez-toc-section-end\"><\/span><\/h3>\r\n    <\/div>\r\n    <div id=\"collapse4\" class=\"panel-collapse collapse in\" role=\"tabpanel\" aria-labelledby=\"heading4\">\r\n        <div class=\"panel-body\" itemprop=\"acceptedAnswer\" itemscope=\"\" itemtype=\"http:\/\/schema.org\/Answer\">\r\n            <div itemprop=\"text\">\r\n                Disk Utility itself does not recover lost data. It is primarily used for repairing file system errors and managing disk partitions. To recover lost files from a drive that Disk Utility can recognize but cannot repair, you would need to use data recovery software or services.\r\n            <\/div>\r\n        <\/div>\r\n    <\/div>\r\n<\/div>\n<div class=\"panel panel-default\" itemprop=\"mainEntity\" itemscope=\"\" itemtype=\"http:\/\/schema.org\/Question\">\r\n    <div class=\"panel-heading\" role=\"tab\" id=\"heading5\" aria-selected=\"true\">\r\n        <h3 class=\"panel-title\" itemprop=\"name\"><span class=\"ez-toc-section\" id=\"what_are_the_best_third-party_tools_for_external_hard_drive_repair_on_mac\"><\/span>\r\n            <a role=\"button\" data-toggle=\"collapse\" href=\"#collapse5\" aria-expanded=\"true\" aria-controls=\"collapse5\">\r\n                What are the best third-party tools for external hard drive repair on Mac?\r\n                <i class=\"fas fa-plus\"><\/i>\r\n            <\/a>\r\n        <span class=\"ez-toc-section-end\"><\/span><\/h3>\r\n    <\/div>\r\n    <div id=\"collapse5\" class=\"panel-collapse collapse in\" role=\"tabpanel\" aria-labelledby=\"heading5\">\r\n        <div class=\"panel-body\" itemprop=\"acceptedAnswer\" itemscope=\"\" itemtype=\"http:\/\/schema.org\/Answer\">\r\n            <div itemprop=\"text\">\r\n                When it comes to external hard drive repair on a Mac, several third-party tools stand out:<\/p>\n<ul>\n<li><strong>Disk Drill<\/strong>. A powerful data recovery tool that also offers disk health monitoring.<\/li>\n<li><strong>TestDisk<\/strong>. An open-source utility for lost partitions recovery and file systems repair, ideal for users with some technical know-how.<\/li>\n<li><strong>PhotoRec<\/strong>. Often used alongside TestDisk to recover lost files from damaged drives.<\/li>\n<li><strong>DriveDx<\/strong>. This tool monitors drive health using S.M.A.R.T. data.<\/li>\n<li><strong>TechTool Pro<\/strong>. An all-embracing diagnostic and repair tool that offers drive repair, optimization, and recovery options, along with performance testing.<\/li>\n<\/ul>\n\r\n            <\/div>\r\n        <\/div>\r\n    <\/div>\r\n<\/div>\n<\/div><\/section>\n","protected":false},"excerpt":{"rendered":"<p>A corrupted external hard drive poses a serious problem for Mac users, often leading to error messages, blocked file access, or sluggish performance. We\u2019ll walk you through different ways to fix a corrupted external hard drive on your Mac, using tools and features already built into macOS, as well as third-party apps. These steps should [&hellip;]<\/p>\n","protected":false},"author":33,"featured_media":1588,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"_lmt_disableupdate":"no","_lmt_disable":"","footnotes":""},"categories":[90],"tags":[],"slider-tags":[],"class_list":["post-6917","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-how-to"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v24.6 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>How to Fix a Corrupted External Hard Drive on Mac: A Full Guide<\/title>\n<meta name=\"description\" content=\"Check out our step-by-step guide on repairing a corrupted external hard drive on a Mac, from basic troubleshooting to advanced recovery.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"How to Fix a Corrupted External Hard Drive on Mac: A Full Guide\" \/>\n<meta property=\"og:description\" content=\"Check out our step-by-step guide on repairing a corrupted external hard drive on a Mac, from basic troubleshooting to advanced recovery.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/\" \/>\n<meta property=\"og:site_name\" content=\"InsanelyMac Blog - Mac and iOS Reviews\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.insanelymac.com\/blog\/wp-content\/uploads\/2021\/05\/How-to-Recover-Deleted-Files-on-Your-Mac.jpg\" \/>\n\t<meta property=\"og:image:width\" content=\"1920\" \/>\n\t<meta property=\"og:image:height\" content=\"300\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\n<meta name=\"author\" content=\"Oleksandr Lukashyn\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Oleksandr Lukashyn\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"24 minutes\" \/>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"How to Fix a Corrupted External Hard Drive on Mac: A Full Guide","description":"Check out our step-by-step guide on repairing a corrupted external hard drive on a Mac, from basic troubleshooting to advanced recovery.","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/","og_locale":"en_US","og_type":"article","og_title":"How to Fix a Corrupted External Hard Drive on Mac: A Full Guide","og_description":"Check out our step-by-step guide on repairing a corrupted external hard drive on a Mac, from basic troubleshooting to advanced recovery.","og_url":"https:\/\/www.insanelymac.com\/blog\/fix-corrupted-external-hard-drive-mac\/","og_site_name":"InsanelyMac Blog - 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