The last couple times I've tried to run virus scans with Avast! I've been getting this message, both times with different files. I have no idea what it means and Googling around doesn't seem to help, so... well, the end result is I'm really worried something might be going wrong with my computer.
Scan Run 17/2/12:
C:\Users\All Users - Error: The system cannot find the path specified (3)
Scan Run 18/2/12:
c:\programdata\microsoft\windows defender\definition updates\...\mpengine.dll - Error: The system cannot find the path specified (3)
I've been using Avast! for two or three years now, on several different machines, and have never encountered this message or had any problems with scans skipping files before. I can't help but feel worried about what may be causing this to happen all of a sudden. What's going on and how can I fix it?