I purchased the pro version complete, but I am disappointed that the program has slowed flashy window xp. I hope the update will come soon.
best regards
Was this the first time you used/installed avast ?
If so - Have (or did) you another Anti-Virus installed in this system, if so what was it and how did you get rid of it ?
If not and you upgraded from avast free - It may be best to try a clean install of avast Pro.
###
What other security software do you have installed (firewall, anti-spy/malware applications) ?