Your USB flash drive might be damaged or something went wrong when you created it.I am trying to install Monterey (12.7.4) via OCLP onto a 2011 iMac. I made an installer using OCLP 241 but it will not install. The internal hard drive is erased and formatted APFS. It was originally running High Sierra.
Whenever I boot the flash drive into the recovery (I assume) where I get the install option it fails after choosing the drive to install on.
Error: "An Error occurred while Preparing the installation. Try running this application again."
Also I have no wifi (no routers listed, nor connect via using name) when I boot using the OCLP EFI boot so this might be a reason the update wont proceed? I don't know. When I boot into the native recovery Wifi connects works fine, so obviously OCLP is causing this somehow.
So I am stuck right now as all I have is the OCLP created USB flash drive with a Monterey installer. On the 'native' iMac recovery boot it never contacts the recovery software server so fails every time to reinstall High Sierra.
Any suggestions regarding how to proceed from here?
Thnx
Hi...Seriously struggling with trying to boot Monterey on my MBP9,1, latest OCLP (can downgrade if culprit).
First tried to install Monterey on a second volume alongside latest 10.15. Went fine until I installed OCLP to disk after the first boot. Subsequent attempts to boot did not work, always hung immediately on the loading screen.
Booting back into 10.15 revealed an error message stating "Failed to find the root snapshot". I followed the 'Stuck on boot after root patching' troubleshooting instructions, but there isn't a root snapshot or any extra problematic kexts.
I recreated the USB installer with a new download of Monterey and OCLP, this time wiping the whole internal drive to just install Monterey onto after installing Catalina as a base. I am getting the same problem: First boot into OS works fine, installing OCLP to disk means no more booting.
Booting into recovery I can see there is a snapshot...but it is 0KB. I presume this doesn't qualify. Have ran first aid but it doesn't seem to help.
What should I do? Why is this happening?
Open Core Legacy Patcher installed with Monterey on Mac Pro 5.1
Starting up the Mac it shows the systems installed but only the Monterey startup, when chose Mojave or other version appears this the symbol…
The way to open the system that I need (Monterey always start) is to plug the drive with that system.
What I done wrong????
By the way, cloning the drive with CCC to another drive the system works well?
Having in the SSD Mojave and Monterey works good?
Thank’s
Thanks!!!!!1st thing, OCLP does not support earlier releases than BigSur. 2nd thing, OCLP spoofs 2019 Mac Pro for running unsupported macOS releases with MacPro5,1, since 2019 Mac Pro only runs Catalina 10.15.1 and newer you can't run earlier releases of macOS when spoofing the MacPro7,1.
To run Mojave you need to bypass OCLP via Apple native BootPicker or manually modify the config.plist to add the bootarg -no_compat_check. You can also modify the config.plist to change the spoofing for iMacPro1,1, but this will create issues with a 2nd display.
If you don't know how to add a bootarg, use the search to find this in more detail.
By the way, cloning the drive with CCC to another drive the system works well?
Having in the SSD Mojave and Monterey works good?




Can you explain why the old original AMD 5870 video card is working on Monterey?
Not even a metal card?
So this is what I found on Github.I think youtube is mostly CPU video decode. Browsers are also easiest to work especially none Safari. Chrome for example carry all the web code with the browser. I think Safari depends on some web code buried in the macOS.
None metal cards have visual anomolies (macOS UI based on metal started using transparencies in windows) on OCLP newer macOS than originally supported ( See 2009-11 21.5" - 27" section in this link ) along with metalized apps (each successive newer macOS metalized more and more standard macOS apps) not working (I think Maps + others (I don't have a full list) don't know if OCLP devs resolved (or can reasonably resolve) these)
So this is what I found on Github.
Legacy Non-Metal GPUs and macOS Big Sur - Sequoia #108
It appears they do have hardware acceleration on this ATI 5870 / TeraScale+2
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Legacy Non-Metal GPUs and macOS Big Sur - Sequoia · Issue #108 · dortania/OpenCore-Legacy-Patcher
Thanks to recent developments in the community and great work from @asentientbot and the Moraea team, we've made great progress on GPU Acceleration support. GPU Acceleration Hardware Support NVIDIA...github.com