Hi Vlk, good guess there. I also suspect that must have been the problem. A hidden error message window saying “avast! cannot scan password protected files”. I am pretty sure that day it didn’t get caught for Alt+Tab. Much appreciated your time for solving this issue with me. :slight_smile:

Anyways, I have to point out ALWIL that user interaction is too much with avast!.
If avast! cannot scan password protected files it doesn’t have to show a MessageBox everytime saying that it cannot scan password protected files.
Another example is this: http://forum.avast.com/index.php?topic=10884.0.

Cheers,
McoreD