There is a workaround to these graphical artefacts remnants of menus, etc. that you could give a try.
Edit avast4.ini using Notepad [Common] section, add the following line to the section SunbeltKPFHack=2, save the file, you will be prompted by the avast! self-defence module if this is OK answer Yes.
See http://forum.avast.com/index.php?topic=37609.msg315764#msg315764
Anyway Windows won’t let me replace the original file with the modified one. This probably because it is opened by a running application.
So, what do I do next?
It would seem to me that for a company like Alwil Software to release an application with a very visible and irritating bug like this one is rather bad form! One would expect Alwil to fix the problem as soon as possible.
No. You need to add that line in the [Common] section, not in the [VRDB].
It’s not really a bug, but a problem that occurs in some computers, with some applications installed, with some hardware configurations. That is not a “solution” but more a “workaround”.