rundll activation

XP PRo svc pak 2

I have something on my computer that calls rundll (as reported by PREVX) and
either starts a copy of IE or it will open another IE window. The most I
have seen is 81 IE windows opened by this virus.

I have run spybot, hijack this, prevx and have Norton AV upto date and the
Yahoo spybot toolbar up to date and run several times. (takes 90 minutes
for Norton, but it does not find anything)

What can this be that is so hidden that none of these programs can find it?
The help desk at Yahoo said to reinstall IE, but it is something in my
machine that is calling RunDLL to get IE started. The address box always
takes me to the login page of yahoo for the email page.

Need Help!
TIA


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