How old is your Windows installation? When was the last clean setup?
Maybe the file ownership got corrupted. You can regain ownership by running this in an admin command prompt:
takeown /f C:\Users\rroli\*.* /r /d y
icacls C:\Users\rroli\*.* /grant administrators:F /t
You can run this where ever you feel it is needed, but never run it on system directories!
Some background info: