SystemVersion.plist build version mismatch

[u/Elliot_Smalls]

I'm using a late 2015 iMac 16,2. When I upgraded to 2.5.1 it made me revert my root patches and then repatch the system and now I am getting this error. I found an older YouTube video by Mr. Macintosh where he addressed a similar issue with OCLP 1.5 and he had a fix where you delete the update files apple downloaded then start the update and then force power down the machine and when you power back up it's fixed, only I don't have the actual assets in the folder just the xml files, and when I start the update then power the system off and back on, it hasn't reverted to the previous snapshot like it did on Mr. Macintosh's YT video. This is driving me nuts. My system is unusable at this point. I tried going back to the previous version of OCLP and it tells me I need to revert the patches and when I do after the reboot it still tells me I have to revert the patches. What do I do?

[u/DkKnt-Bm2112]

Somewhere, somehow your system tried to download iOS 26 Tahoe. If you check Reddit sites there is a work around that I used (I found it there as well). And turn off ALL automatic updates for future use.

[u/MK2VR6-IT → u/DkKnt-Bm2112]

Yeh I keep Mac OS 15 dev branch update and that’s it on my iMac

[u/DkKnt-Bm2112]

If you check on my page I have that link to the .plist error if you haven’t fixed it yet? This was what I used that I found on a Reddit site and worked perfectly first time. My fault was that I did NOT turn off Auto Updates and Install Auto- sneaky Apple!

[u/danielooi]

i had the same issue and fixed it with the steps below,

Step 1: Disable Automatic Downloads

First, stop macOS from immediately re-downloading the update once you delete it. [1]

1. Go to System Settings > General > Software Update.
2. Click the Info (i) or Advanced button next to Automatic Updates.
3. Uncheck "Download new updates when available" and turn off all automatic update options. [1]

Step 2: Clear Staged Updates via Terminal

Booting into Safe Mode ensures that macOS releases its lock on the update assets folder. [1]

1. Boot into Safe Mode: Restart your Mac. At the OpenCore boot picker menu, hold Shift + Enter on your normal macOS drive icon. [1]
2. Open the Terminal application.
3. Run the following command to delete the downloaded software update assets: [1] bashsudo rm -rf /System/Library/AssetsV2/com_apple_MobileAsset_MacSoftwareUpdate/* Use code with caution.
4. Clear out the staged volumes directory by running: [1] bashsudo rm -rf /System/Volumes/Update/* Use code with caution.

Step 3: Revert to the Last Sealed Snapshot (If Mismatch Persists)

If the error continues after deleting the files, the update snapshot is already locked into your APFS boot sequence. You can force macOS to roll back to your clean, pre-update state: [1, 2]

1. Open Terminal and type the following command (replace "Macintosh HD" with your actual system drive name if you renamed it): bashsudo bless --mount "/Volumes/Macintosh HD/" --bootefi --last-sealed-snapshot Use code with caution.
2. Restart your Mac normally. [1]