We get below patch roll back message on our Windows Server 2012 R2 DC servers
The error “we couldn’t complete the updates undoing changes Windows 10” occurs due to the following possible causes
Lack of enough free disk space
The update is interrupted during the installation process.
Corrupted system files
You can try the following steps
Run DISM and SFC Tools
Delete the contents of the SoftwareDistribution Folder
Reset update components
Repair update the PC
Run the Windows Troubleshooter
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