[Pre Release] macOS Tahoe 26.4

[Zevgoli]

I get this permission denied screen trying to upgrade to OCLP 3.1.5 after upgrading to 26.4.  Any ideas?

 

Cheers, Howard

 

[deeveedee]

25 minutes ago, fabiosun said:

Sorry i wrote bad, it is a Raid 0 with two Nvme 2Tb each one

Ok.  what RAID 0 solution are you using with macOS?

 

EDIT: Are you simply using the RAID 0 configuration in disk utility?  What kind of performance gain are you experiencing?  Thanks.

Edited February 17 by deeveedee

[fabiosun]

@deeveedee yes simply raid0 done in disk utility

No improvement from latest OSX i tried

in the past about 80% faster than one same disk solution

Now in Sequoia or in Tahoe zero improvment in performance

 

[Max.1974]

https://swcdn.apple.com/content/downloads/06/63/047-01208-A_J3XEK7LLH9/sr0z5l26rpsvur2gim4d5z1ry8kmd4r2cc/InstallAssistant.pkg 

 

[ 26 ] 2026-02-17 18:20:47 .. 047-01208 .. 26.4.0.25E5207k macOS Tahoe Beta

[Stefanalmare]

9 hours ago, Stefanalmare said:

Anyone with this problem? OCLP 3.0.0 Nightly and OCLP-Mod 3.1.4, the same.

 

  Reveal hidden contents

 

 

OCLP-Mod 3.1.5 give NVME KP. Had to restore last sealed snapshot.

[LockDown]

On 2/17/2026 at 4:29 AM, Shikumo said:

sudo mount -w -t hfs /dev/diskXsY /Volumes/HFSDISK

sudo mount -uw /Volumes/xxx && killall Finder

 

How to make this as automator?

Edited February 18 by LockDown

[johnnyl]

I keep getting Stuck on apple loading page after installing OCLP-Mod 3.1.5. How can I manually remove all trace of OCLP-Mod to start fresh again. I think I messed up reverting the patches.

Ive had to reinstall 26.4 to get back into Tahoe desktop but after doing the Mod patches it just gets stuck on reboot..

Edited February 18 by johnnyl

[laobamac_yyds]

I think I have described it very clearly in the update content, do not install any patches that require KDK! That is to say, currently only the classic launchpad patch and wireless network card patch are available for 26.4B1

Edited February 18 by laobamac_yyds

[verdazil]

On 2/17/2026 at 6:25 AM, Slice said:

So 26.4 cancel support for HFS+?

Here are the arguments suggesting that HFS+ support is likely to remain:

In the current beta of macOS Tahoe, the system still allows creating HFS+ volumes in Disk Utility.

The HFS+ formatting process completes successfully, which indicates that the filesystem implementation is still present.

The issue appears limited to mounting newly created volumes via the graphical interface, rather than a complete removal of HFS+ functionality.

Apple has not announced any official deprecation or removal of HFS+ support.

Taken together, this suggests the behavior is more likely a beta bug than an intentional removal of HFS+ support.

[deeveedee]

11 minutes ago, verdazil said:

Taken together, this suggests the behavior is more likely a beta bug than an intentional removal of HFS+ support.

Agreed.  We've been here before with previous Beta versions of macOS.  Recall that some actually created utilities to "fix" the problem before Apple restored normal HFS+ behavior in a subsequent Beta.

[MaLd0n]

[johnnyl]

14 hours ago, laobamac_yyds said:

I think I have described it very clearly in the update content, do not install any patches that require KDK! That is to say, currently only the classic launchpad patch and wireless network card patch are available for 26.4B1

Thanks for highlighting that. I missed it.

[Ludox]

As I said before "DO NOT INSTALL" you will have a lot of problems, wait for the second Build

[deeveedee]

No offense, but "Do not install" makes me want to install it even more    

 

If you're testing Betas in a volume that's not expendable, you might want to rethink that.  Just create a new APFS volume and install your Betas in that sandbox.  Then, when you're satisfied with the new version, upgrade your "production" volume.  Keeping separate volumes for test and production eliminates a lot of problems.

 

There is no reason to avoid new releases (Beta or otherwise) if you are playing with the newest untested version in an expendable Volume that you can erase/delete if necessary.

[LockDown]

6 hours ago, deeveedee said:

Agreed.  We've been here before with previous Beta versions of macOS.  Recall that some actually created utilities to "fix" the problem before Apple restored normal HFS+ behavior in a subsequent Beta.

One thing i noticed is...

If the drive is formatted as HFS+ in 26.4, the drive won't be mounted. It stays unmounted even after restart, and no error prompt will popup.

But if its formatted as HFS+ in lower macOS build, it will mount with the error prompt

[Max.1974]

Hello colleagues, some time ago I created a few tools to eventually replace macOS Disk Utility formatting with an independent solution. So far it has been formatting in HFS+ and I was able to write a DMG image that I created for emergency use in case this happened. It worked well on Tahoe 26.4. However, since this is experimental, I still believe it could be some issue with the Tahoe 26.4 release. I managed to create a bootable disk as if it had been made with Balena Etcher, because macOS would not allow Balena Etcher itself to open.

 

 

 

 

Finish 100% 

 

 

Image .img (Raw) was created before with my another app (in older macOS version from Tahoe) 

 

 

Image burned boot up and works 100% 

 

 

 

 

 

 

 

Edited February 19 by Max.1974

[laobamac_yyds]

2 hours ago, LockDown said:

One thing i noticed is...

If the drive is formatted as HFS+ in 26.4, the drive won't be mounted. It stays unmounted even after restart, and no error prompt will popup.

But if its formatted as HFS+ in lower macOS build, it will mount with the error prompt

At present, HFS+related drivers still exist in/S/L/E and can theoretically still be used. But we cannot speculate whether HFS will be completely abandoned in the subsequent official version through Beta1.

 

But personally, I don't think Apple would “upgrade” a file system's compatibility in a way that breaks it—APFS disks created under Catalina, for instance, can still be used directly to this day. Since macOS 26.4 now indiscriminately reports errors with the legacy HFS+ format, it suggests that this format is either about to undergo a major overhaul or will be phased out entirely. (The above is just my personal opinion.)

Anyway, using APFS now is a more secure approach.

 

[Max.1974]

Works fine and recognize installer created from .img 

 

[verdazil]

28 minutes ago, laobamac_yyds said:

Anyway, using APFS now is a more secure approach.

It’s hard to disagree with that. For the system partition, we use the APFS file system and have no alternative. For a data drive, access time and read/write speeds are not critical. Switching to APFS does not have any negative consequences. The only drawback that comes to mind is that reading from and writing to APFS in Linux is somewhat more complicated than with HFS+.

 

42 minutes ago, laobamac_yyds said:

it suggests that this format is either about to undergo a major overhaul

Doesn’t a major upgrade require full backward compatibility? For example, USB 2.0 devices work perfectly fine in USB 3.0 ports.

[laobamac_yyds]

18 minutes ago, verdazil said:

It’s hard to disagree with that. For the system partition, we use the APFS file system and have no alternative. For a data drive, access time and read/write speeds are not critical. Switching to APFS does not have any negative consequences. The only drawback that comes to mind is that reading from and writing to APFS in Linux is somewhat more complicated than with HFS+.

 

Doesn’t a major upgrade require full backward compatibility? For example, USB 2.0 devices work perfectly fine in USB 3.0 ports.

I see your point now—hardware and software can't really be compared directly. If we push that analogy, then USB 1.0 is also compatible with USB 3.0.

 

It seems the translation tool may have misinterpreted what I meant earlier. What I was trying to say is that it's unlikely for macOS to alter something in a way that "breaks compatibility" just for the sake of change. So, if HFS+ is being flagged with errors indiscriminately in 26.4, it probably means the format will either be completely overhauled—so thoroughly that it's essentially something new—or it will be removed altogether.

[johnnyl]

I have a SSD Drive with 4 HFS partitions. Would it be safe to just use Disk Utility to convert them to APFS without any Data loss to get round this HFS fault in 26.4 ? Obviously I would back up before attempting this.

[verdazil]

5 minutes ago, johnnyl said:

I have a SSD Drive with 4 HFS partitions. Would it be safe to just use Disk Utility to convert them to APFS without any Data loss to get round this HFS fault in 26.4 ? Obviously I would back up before attempting this.

I would wait for the official release of 26.4. Perhaps the bug will be fixed.

[johnnyl]

52 minutes ago, verdazil said:

I would wait for the official release of 26.4. Perhaps the bug will be fixed.

That sounds wise. Hopefully there will be a fix.

[fabiosun]

I did with 0 problems (but also it is safe to backup)

I did with 26.3 recovery because 26.4 recovery had errors while converting disks in Diskutility convert to apfs menu

Edited February 19 by fabiosun

[laobamac_yyds]

Anyway, I still hope this is an accident that occurred in B1...

 

I don't understand why Apple need to adjust HFS+, a widely used and time spanning file system.

Edited February 19 by laobamac_yyds