try this
ad-aware I use XP pro as well and have never come across/heard of this issue.
if that doesn's work, check your IE settings (internet options) in advanced make sure the following are checked.
always send urls as utf-8
enable page transitions
security----
use ssl 2.0
use ssl 3.0
use tls 1.0
also, try clearing your cache, run a scandisk and try defragging. a lot of times if I have errors or probs with IE a defrag helps, i dunno why.