OpenCore Legacy Patcher in iMac Pro running Sequoia / Catalina causing endless reboot. Need help!

[timidhermit]

I am fully aware that my iMac Pro natively supports macOS Sequoia (and obviously Catalina). However, I want to install OpenCore Legacy Patcher because I want to leverage OCLP's ability to protect the system EFI when I create an extra partition using Disk Utility to install Windows 11 and not risk damaging the system EFI over time. I am running into the following problems:

1, In the OCLP's main menu, the option to "Build and Install OpenCore" cannot be clicked on. I have to go to Settings, enable Allow Native Models in the App tab, in order to the option to be available.

Once OCLP has prepared the patch, I allowed it to write to the EFI partition on the system's drive. When I rebooted, however, the machine just rebooted endlessly with the Apple logo.

I used OCLP to create an macOS Sequoia USB Installer. I followed the same above step to patch the EFI partition on the USB Installer. However, when I tried to install macOS using this USB Installer (system already set to allow to boot to external USB) after selecting EFI boot, the system also goes into an endless boot loop with the Apple logo.

I suspect that I am encountering this problem because of the T2 chip in the iMac Pro.

Can someone help?

 

[Bigwaff]

I suspect that I am encountering this problem because of the T2 chip in the iMac Pro.

Can someone help?

Probably not. OCLP doesn’t support T2 Macs. You gone done something wAcKy. No boot for you!

macOS Sequoia and OpenCore Legacy Patcher Support · Issue #1136 · dortania/OpenCore-Legacy-Patcher

Another year, another WWDC and macOS version. This time with macOS 15, Sequoia, and a surprising lack of dropped hardware compared to previous years 🎉. As the OS has been in developer beta for a fe...

github.com

 

[timidhermit]

Probably not. OCLP doesn’t support T2 Macs. You gone done something wAcKy. No boot for you!

macOS Sequoia and OpenCore Legacy Patcher Support · Issue #1136 · dortania/OpenCore-Legacy-Patcher

Another year, another WWDC and macOS version. This time with macOS 15, Sequoia, and a surprising lack of dropped hardware compared to previous years 🎉. As the OS has been in developer beta for a fe...

github.com

I am aware T2 support in OCLP is limited. However, I have read many other threads elsewhere of T2 Macs running OCLP on Sequoia and even Tahoe (with even more limited support).

Also, if it is not entirely supported, how come OCLP can build a profile for iMacPro1,1 (my iMac) and offer it to install to the EFI partition.

I feel I am missing something else... rather than just a non-support issue.

 

[Bigwaff]

I am aware T2 support in OCLP is limited. However, I have read many other threads elsewhere of T2 Macs running OCLP on Sequoia and even Tahoe (with even more limited support).

Also, if it is not entirely supported, how come OCLP can build a profile for iMacPro1,1 (my iMac) and offer it to install to the EFI partition.

I feel I am missing something else... rather than just a non-support issue.

Direct quote from the link I provided -
"We have made some progress on this issue, but panics are still occurring and there is still a significant amount of development work to do before T2 machines may even get to the install screen. We cannot provide any estimate on when T2 machines will be supported." Doesn't sound to me like support "is limited".

I have a MacBook Neo. When I launch OCLP application, I see "Model: Mac17,5" (which is correct for the Neo), however, we know Apple Silicon Macs are not supported target host models. If I click settings and open the Host Model drop-down, I do not see your iMacPro1,1 in the list of supported target host models. Do you?

 

[timidhermit]

Direct quote from the link I provided -
"We have made some progress on this issue, but panics are still occurring and there is still a significant amount of development work to do before T2 machines may even get to the install screen. We cannot provide any estimate on when T2 machines will be supported." Doesn't sound to me like support "is limited".

I have a MacBook Neo. When I launch OCLP application, I see "Model: Mac17,5" (which is correct for the Neo), however, we know Apple Silicon Macs are not supported target host models. If I click settings and open the Host Model drop-down, I do not see your iMacPro1,1 in the list of supported target host models. Do you?

Thanks for the clarification, Bigwaff. I appreciate your guidance. 🙂

You are correct. As implied in my original post, I do not see iMacPro1,1 among the list of supported target host models. I have to go to Settings and enable Allow Native Models in the App tab to force OCLP to create "supposedly" a profile for iMacPro1,1 to install to the EFI partition.

Based on what you said, am I correct to assume whatever profile OCLP claimed to have build for iMacPro1,1 is completely BS? It seemed in hindsight that OCLP had not even created any working EFI partition to install despite the app reported that it had created the profile and had written to the partition.

So confused now!

 

[Bigwaff]

Based on what you said, am I correct to assume whatever profile OCLP claimed to have build for iMacPro1,1 is completely BS? It seemed in hindsight that OCLP had not even created any working EFI partition to install despite the app reported that it had created the profile and had written to the partition.

So confused now!

Unfortunately, OCLP application won't stop you from generating an EFI which will bork the target Mac... even supported target Macs. I guess you can always search and ask over on the Discord. Perhaps issues are related to the version of OCLP application you are using. You never mentioned which version of OCLP application... and, unfortunately it must be asked as there are forks and malware masquerading as OCLP application, where you downloaded it from.

 

[timidhermit]

Unfortunately, OCLP application won't stop you from generating an EFI which will bork the target Mac... even supported target Macs. I guess you can always search and ask over on the Discord. Perhaps issues are related to the version of OCLP application you are using. You never mentioned which version of OCLP application... and, unfortunately it must be asked as there are forks and malware masquerading as OCLP application, where you downloaded it from.

Version 2.4.1. Official. Not forked.

I will try to search for the OCLP Discord server. Good idea, Bigwaff!