Ok are you running sp2? if so use the windows firewall with avast maybe as running without a A/v isnt safe
it does look like your not alone with this kind of problem
http://www.dslreports.com/forum/remark,13189661~reverse=0;days=10;root=security;mo de=full
dunno if this is relevent or not
http://forum.grisoft.cz/freeforum/re...?2,25532,25604