Had the same problem with a Toshiba Laptop which turn out to be the mydooom virus. Downloaded the free tool from syamntec web site and followed instruction precisely as you have to remove the virus twice once in normal and then in safe mode. it's quite a nasty criter. I hope this helps.
The person that got this had
no firewall software loaded zonealarm free
out of date virus guard updated free
no spyware sofware load spybot free but contribute to up keep
windows 2000 sp1 no hot fixes ????? windows update free
They thought they were safe on a pstn connection hmm
Totally avoidable its like driving your car without a seatbelt on.