StopZilla is an awesome program right out of the box. There are virtually no settings to play with, just a couple buttons to allow/disallow pop-ups. However, I've had problems with Stopzilla on my Windows XP pro install. Explorer keeps bombing out on me, and restarting. When I check event viewer, There is an event stating that explorer had errors and had to be restarted, and referenced to the faulting module: is3core.dll. I did some searches and didn't find much until I ran into an article about StopZilla which refererenced is3core.dll. I guessed that the only solution at the time was to remove Stopzilla, which is a bloody shame because I think it is the best pop-up blocker I've seen to date. After the de-install of StopZilla, my problems went away. Anyway, I'm going to research this further, and hopefully find a fix for the problem, as I totally recommend this production besides the fault that it had.