File Backups Stopped Working after Windows 11 KB5083769 Undate

Found a workaround, restart these 3 services in Powershell:

Restart-Service -Name "EventSystem" -force
Restart-Service -Name "VSS"
Restart-Service -Name "UrBackupClientBackend"

You can save that as a .ps1 script and then make a scheduled task to run at startup (I added 1 min delay) with

with parameters

-ExecutionPolicy Bypass <your_script_path>