Try uninstalling avast! and see if that works. Report back here.
nope, troubleshoot first >>> start by disabling (temporarily) self-defense protection and do your restore in safe mode. If that still doesn't work (which I doubt) remove the behavior shield and reboot, then try again.
ps: well usually the behavior shield can be an issue for restore point creations, not for restoring. The main issue when restoring remaining, as said, the self defense module.