it sounds like you may have a trojan of some sort, i had a problem like this, run spybot search and destroy, adaware, stinger, and go to trend micro for an online scan, here are some links for you.
http://housecall.trendmicro.com/hous...start_corp.asp http://vil.nai.com/vil/stinger/ http://www.safer-networking.org/en/index.html http://www.download.com/3000-2144-10...age&tag=button
scan with these and your system will be clean !
hope this helps
ps.
get rid of norton and get A.V.G. free version, go here
http://www.grisoft.com/us/us_index.php
pps.
dont forget to turn system restore off before scanning