snifferdog27 Posted September 25, 2025 Share Posted September 25, 2025 Hi, posting here as a new user (well, my old account disappeared...) since this seems to be the only place allowed. Since the latest 'Mac' supported by my hardware is a 2019 iMac, Tahoe doesn't officially support it. I got round this by downloading the installation package from Mr Macintosh and that ran fine. Tahoe also runs faultlessly. However, I am not offered updates - 'check for update' always says I am on the latest version, even though I enrolled my Mac for the Beta program and made sure that SIP is enabled. Again, I downloaded the Beta package from Mr Macintosh and got it installed, but the situation is not ideal. Anyone know how to get round this? I tried setting SystemProductName to iMac20,1 in config.plist but my machine is still reported as a 2019 iMac in 'About this Mac' and updates are still not offered. Thanks. Quote Link to comment https://www.insanelymac.com/forum/topic/361738-how-to-get-tahoe-system-updates-working-on-coffee-lake/ Share on other sites More sharing options...
tikizondo94 Posted September 26, 2025 Share Posted September 26, 2025 Upload your EFI and ill take a look. Quote Link to comment https://www.insanelymac.com/forum/topic/361738-how-to-get-tahoe-system-updates-working-on-coffee-lake/#findComment-2841317 Share on other sites More sharing options...
deeveedee Posted September 26, 2025 Share Posted September 26, 2025 (edited) @snifferdog27 Does your hack have multiple physical drives? If so, is it possible that you have more than one boot-loader EFI and that you're not booting from the EFI that you think you are? If not, like tikizondo94 said, can't offer much help without seeing your boot-loader EFI. @snifferdog27 Another thought - if you changed only the SystemProductName in your config.plist, that is insufficient for changing SMBIOS. Edited September 27, 2025 by deeveedee Quote Link to comment https://www.insanelymac.com/forum/topic/361738-how-to-get-tahoe-system-updates-working-on-coffee-lake/#findComment-2841320 Share on other sites More sharing options...
JorgeMax Posted September 26, 2025 Share Posted September 26, 2025 On 9/25/2025 at 12:06 PM, snifferdog27 said: Hi, posting here as a new user (well, my old account disappeared...) since this seems to be the only place allowed. Since the latest 'Mac' supported by my hardware is a 2019 iMac, Tahoe doesn't officially support it. I got round this by downloading the installation package from Mr Macintosh and that ran fine. Tahoe also runs faultlessly. However, I am not offered updates - 'check for update' always says I am on the latest version, even though I enrolled my Mac for the Beta program and made sure that SIP is enabled. Again, I downloaded the Beta package from Mr Macintosh and got it installed, but the situation is not ideal. Anyone know how to get round this? I tried setting SystemProductName to iMac20,1 in config.plist but my machine is still reported as a 2019 iMac in 'About this Mac' and updates are still not offered. Thanks. Try to do this: Change the SMBIOS to iMac20,1 or 20.2. Add the kext “RestrictEvents” and on the NVRAM place in this location: 4D1FDA02-38C7-4A6A-9CC6-4BCCA8B30102 the key “revpatch” string “sbvmm”. Restart and try to check if you find the updates. At the time I had this problem and it solved it. Quote Link to comment https://www.insanelymac.com/forum/topic/361738-how-to-get-tahoe-system-updates-working-on-coffee-lake/#findComment-2841323 Share on other sites More sharing options...
snifferdog27 Posted October 9, 2025 Author Share Posted October 9, 2025 On 9/26/2025 at 5:55 PM, JorgeMax said: Try to do this: Change the SMBIOS to iMac20,1 or 20.2. Add the kext “RestrictEvents” and on the NVRAM place in this location: 4D1FDA02-38C7-4A6A-9CC6-4BCCA8B30102 the key “revpatch” string “sbvmm”. Restart and try to check if you find the updates. At the time I had this problem and it solved it. Thanks, that worked. 'About this Mac' still reports my machine as a 2019 iMac but updates work as they should. I'm a happy bunny. Quote Link to comment https://www.insanelymac.com/forum/topic/361738-how-to-get-tahoe-system-updates-working-on-coffee-lake/#findComment-2842027 Share on other sites More sharing options...
miliuco Posted October 9, 2025 Share Posted October 9, 2025 @snifferdog27 Please add a signature con the specs of your machine in your account details. Upload here your config.plist file, About This Mac should report 2020 iMac model with both iMac20,1 and iMac20,2 SMBIOS. Quote Link to comment https://www.insanelymac.com/forum/topic/361738-how-to-get-tahoe-system-updates-working-on-coffee-lake/#findComment-2842031 Share on other sites More sharing options...
XanthraX Posted October 10, 2025 Share Posted October 10, 2025 (edited) Hi there, I am still on CofeeLake, I already did the modifications. I wait for a nvME SSD I ordered to arrive. And I try. I still stay on Sequoia until Dortania will make the version of OCLP for Tahoe. But I want to try it on that SSD. I don't think it worth to waste money for other PC, or for a Fullmac wi-fi card (probably it comes in the same time, since dortania will release the version for Tahoe of OCLP, I am always the labrat chose for testing the Murphy's laws lol). I hope the SSD arrives next week and I will keep you updated. Edited October 10, 2025 by XanthraX Quote Link to comment https://www.insanelymac.com/forum/topic/361738-how-to-get-tahoe-system-updates-working-on-coffee-lake/#findComment-2842041 Share on other sites More sharing options...
snifferdog27 Posted October 11, 2025 Author Share Posted October 11, 2025 On 10/10/2025 at 12:34 AM, miliuco said: @snifferdog27 Please add a signature con the specs of your machine in your account details. Upload here your config.plist file, About This Mac should report 2020 iMac model with both iMac20,1 and iMac20,2 SMBIOS. OK, filled in my sig, and here is my config.plist (with my serial number redacted). config.plist 1 Quote Link to comment https://www.insanelymac.com/forum/topic/361738-how-to-get-tahoe-system-updates-working-on-coffee-lake/#findComment-2842110 Share on other sites More sharing options...
miliuco Posted October 11, 2025 Share Posted October 11, 2025 @snifferdog27 I don't see anything weird, did you do ResetNVRAM after changing to iMac20,1? Quote Link to comment https://www.insanelymac.com/forum/topic/361738-how-to-get-tahoe-system-updates-working-on-coffee-lake/#findComment-2842116 Share on other sites More sharing options...
strangeron Posted October 12, 2025 Share Posted October 12, 2025 Could you still be using the SystemSerialNumber/UUID/ from a 2019 iMac? Quote Link to comment https://www.insanelymac.com/forum/topic/361738-how-to-get-tahoe-system-updates-working-on-coffee-lake/#findComment-2842125 Share on other sites More sharing options...
ichelash Posted October 12, 2025 Share Posted October 12, 2025 (edited) 15 hours ago, snifferdog27 said: OK, filled in my sig, and here is my config.plist (with my serial number redacted). config.plist 32.42 kB · 3 downloads Can you add "revpatch=sbvmm" in your boot-args..reboot, reset nvram and see if update will pop up..remove this “revpatch” string “sbvmm” from NVRAM->4D1FDA02-38C7-4A6A-9CC6-4BCCA8B30102. Edited October 12, 2025 by ichelash 1 Quote Link to comment https://www.insanelymac.com/forum/topic/361738-how-to-get-tahoe-system-updates-working-on-coffee-lake/#findComment-2842127 Share on other sites More sharing options...
snifferdog27 Posted October 12, 2025 Author Share Posted October 12, 2025 22 hours ago, miliuco said: @snifferdog27 I don't see anything weird, did you do ResetNVRAM after changing to iMac20,1? Just tried that - no change. Quote Link to comment https://www.insanelymac.com/forum/topic/361738-how-to-get-tahoe-system-updates-working-on-coffee-lake/#findComment-2842147 Share on other sites More sharing options...
snifferdog27 Posted October 12, 2025 Author Share Posted October 12, 2025 12 hours ago, strangeron said: Could you still be using the SystemSerialNumber/UUID/ from a 2019 iMac? Seems I was. I generated new values using gensmbios and the problem is now solved. Thanks to everyone who chipped in. 2 Quote Link to comment https://www.insanelymac.com/forum/topic/361738-how-to-get-tahoe-system-updates-working-on-coffee-lake/#findComment-2842149 Share on other sites More sharing options...
snifferdog27 Posted October 12, 2025 Author Share Posted October 12, 2025 A bit of additional info: I still need RestrictEvents.kext for updates to work. I tried disabling it and when I did that no updates were offered (even though there are some). I tried resetting NVRAM after updating my config.plist but that didn't help. Seems that iMac20,1 is to some extent decorative. Quote Link to comment https://www.insanelymac.com/forum/topic/361738-how-to-get-tahoe-system-updates-working-on-coffee-lake/#findComment-2842150 Share on other sites More sharing options...
miliuco Posted October 13, 2025 Share Posted October 13, 2025 @snifferdog27 RestrictEvents thing is as expected, iMac20,1 has chip T2 so the kext and the boot arg are required to be notified of updates. But it is not decorative, iMac models before 20,1 are not supported by Tahoe. 1 Quote Link to comment https://www.insanelymac.com/forum/topic/361738-how-to-get-tahoe-system-updates-working-on-coffee-lake/#findComment-2842161 Share on other sites More sharing options...
snifferdog27 Posted October 13, 2025 Author Share Posted October 13, 2025 5 hours ago, miliuco said: @snifferdog27 RestrictEvents thing is as expected, iMac20,1 has chip T2 so the kext and the boot arg are required to be notified of updates. But it is not decorative, iMac models before 20,1 are not supported by Tahoe. Understood, thank you. Quote Link to comment https://www.insanelymac.com/forum/topic/361738-how-to-get-tahoe-system-updates-working-on-coffee-lake/#findComment-2842168 Share on other sites More sharing options...
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