Hi, eliezer
You have stated that you did all that . Pl list what you have done so that solution could flow.
It is connected with system files. Did you try sfc /scannow and if so what are the results obtained. Could you run to 100%. please enclose the error log of sfc.
Before that i would recommend chkdsk /f/r to fix system errors.
If this is fixed then you could start update. Did you use the microsoft fix tool for that
Try this if it fixes ok, Type on elevated command prompt
takeown /f C:\Windows\winsxs\pending.xml
and then
Ren c:\windows\winsxs\pending.xml pending.old
This will rename the pending updates and the problem may get solved.
There are so many reasons for this corruption