Hey Gs,
It’s radicalb21. First let me welcome you to the forum. First let me say the current version of Avast is Windows XP SP2 compatible. I have no problems on my system. Let me ask a couple of questions. Did you upgrade to XP SP2 with Avast already installed? It is typically not a good idea to have antivirus software running when upgrading your OS. I would suggest uninstalling avast and reinstalling and that should take care of the problem. Also make sure when you uninstall avast and then you delete the program folder for avast. Also go back and clean out your registry. I hope this helps. Also uninstall the other antivirus as well. It’s not a good idea to have two antivirus programs running in the background. It causes major problems.