On My Spare time I help clean / fix / remove these kind of things from PC's and its starting to get overwhelming, most of the time I dont charge anything. And you dont have to visit Pr0n Sites either to get them, a 3rd Party Advertiser can install malicious software utilizing Microsofts Multiple Holes that are not plugged yet. Sounds like you had a Keylogger, logging your keystrokes and sent them to a hackers listening box. Script Kiddies get their jollys doing this kind of stuff. Unfortunalty these days you can have a PC sitting naked without any protection. I have the luxury of having 2 computers. My high end system is not hooked up to the internet, and its the machine that I do my Music Composing, Bryce, Photoshop and Video Editing. My Slowest system which is what I use to check my e-mail and surf has. McAfee VirusScanner + Giant Company Anti-Spyware (now owned by microsoft). My Firewall is Hardware via a Router. Even if you dont have a network setup at home, I highly recommend purchasing a Router to put between your PC and the Internet. Routers have really dropped down in price, you can buy one for the Same price or cheaper than a Software Firewall Solution. D-Link & Linksys are two that I recommend are very easy to setup. You can limit incoming and outgoing traffic very easily via a web interface.