Funny situation it is

since I've installed this new ATI video card (well, new to me anyways, it's ATI 9200SE) I've put latest drivers from then and never upgraded them. Until now, there were only one driver upgrade from ATI, and these drivers don't support my card anymore, so I didn't installed them. I have Catalyst 6.5 now.
Since then, there were a few Avast updates, and I recall I could read log file before. Now, when I want it to start, either from right-click menu on tray icon or from Avast itself, it doesn't start. And after that, when I make some right-click selection in explorer, I get this:

Can't refresh to clean it, all I can do is log off and log on.
When I log off, I get error that a program is not responding, and it's this one:
ati video bios poller clientI kill it, and suddenly, Log Viewer comes out of darkness

I've tried it several times, and always works that way.
Any help appreciated.
Ivan.