Hi,
let me report my experience with this issue.
First to mention: no Kerio, I never did an install, I use Ashampoo. Installation almost the same time as avast. Before I removed Norton (one poster mentioned this), for me it was Internet Security 2005.
Second - for me I found an easy way to remove the left over or window/program blocking: starting opera web browser.
Freshly booted system (Win XP Home SP2, restricted user)
Right-click on "A", start Log viewer. Process is running (ashLogV.exe), no window appears. Stack Trace (1)
Then right-click on "A", the window is translucent until I move the cursor inside. Any item to start is staying as rectangle (e.g. "Programm Einstellungen...").
Right-click on "A", start Log viewer. Process is running (ashLogV.exe), no window appears. Starting opera brings all up, opera and log viewer! Stack trace (2)
Or start Antivirus, memory test finishing, simple interface is not coming up. Start opera, browser window and simple interface are coming up.
hmmmm...