Software

go to www.panicware.com to download the freeware.

go into your control panel and goto SERVICES... there is a service running called MESSENGER... Stop it, then change the setting to never stop. That program is used on networks to send remote messaging to users when needed. Home users run into the problem of it coming up from spammers trying to sell 1-800..., viagra, enlargement and so forth.

Good luck.

Try the Google toolbar.
http://toolbar.google.com/

i had the same problem for a while i used a few free pop up stoppers but i found the the google toolbar works the best, i have had no problems since.

another vote for the google toolbar! www.google.com, look for the Tools link at the bottom, pick the toolbar. you don't have to enable the advanced features for the pop-up blocker to work. Anti-virus, Google Toolbar, ad-aware, firewall, lightning protection are my stock new computer accessories now...