System repair pending which requires reboot to complete (loop)

You get the following error message when running SFC /scannow even after you reboot?

You might also find on reboot that Windows updates are reverting / failing.

You are stuck every time you run SFC as it keeps telling you to reboot?  Are you windows updates also failing?  Did you ever rename or delete the C:\Windows\SoftwareDistribution folder to fix an issues with windows updates?

Try

https://support.microsoft.com/en-us/help/2509997/you-can-t-install-updates-on-a-windows-based-computer

FIX

The following fix may work but I do not recommend it unless you know what your doing and your prepared for any issues that may occur afterwards.  Do so at your own risk!

Locate your WinSxS folder, usually C:\Windows\WinSxS

Do you have a file called pending.xml and does the date/time match the time you started having issues?

Rename pending.xml to pending.xml.old; in order to do this you must take ownership of the pending.xml file either via Windows Explorer or using takeown.

- Administrator command prompt
- takeown /f C:\Windows\winsxs\pending.xml
- Ren c:\windows\winsxs\pending.xml pending.old

Reboot and try sfc /scannow ….