After being unable to install .NET 3.5 on a clean Windows 10 Pro install, this led me to do a DISM /Online /Cleanup-Image /RestoreHealth which would NOT complete.
Microsoft shipped Creators Update with missing and/or corrupt MUM files (Microsoft Update Manifest, error CBS Corrupt MUM).
Basically involves removing the following Registry entries (you have to give yourself “Full Control” before you can delete them). Backup the keys just in case you ever want them.
- HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Component Based Servicing\PackageIndex\Microsoft-Windows-TestRoot-and-FlightSigning-Package~31bf3856ad364e35~amd64~~0.0.0.0
- HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Component Based Servicing\Packages\Microsoft-Windows-TestRoot-and-FlightSigning-Package~31bf3856ad364e35~amd64~~10.0.15063.0
Confirm in an elevated command prompt:
dism.exe /online /cleanup-image /restorehealth
I would suspect millions of Windows 10 Creators Update 64-bit machines suffer this issue and can’t properly add/remove Windows features or repair using DISM.