Undetectable Virus?

OK, so awhile ago I got a virus, which my scanner couldn't find. I came here and asked about it, and got alot of help. I got rid of the virus, and was alot more careful. But now it seems to have happened again (I really don't know how I'm getting these viruses...). I went back to my old topic and none of the ideas work. I used Windows Live Onecare, Avast! anti-virus, and Ruguefix (or something like that), but to no avail. The virus isn't too bad, but its still annoying...well I'm pretty sure its a virus. I keep getting this pop-up (http://www.system-defender.com/freeware/... for System Defender. I have no clue how reliable it is, but I don't trust it, since its a POP-UP and it wiggled through my Firewall. My internet has also slowed down alot, and for some reason my recycling bin is...broken. The little icon is there, but "Recycling Bin" is not under it and I can't open it. So if it a virus, how do I get rid of it. If it isnt, what's w/ bin?

Undetectable Virus?ktm

You definitely have a virus.The Ad-Ware Alert that Debra recommended is also a rouge anti-spyware program, DO NOT GET IT!! Also, sometimes the virus could have infected the System Resotre restore points, rendering it useless. Since most free anti viruses dont work as well as paid ones, try getting a free trial of NOD32. Make sure to uninstall your other anti virus for they might interfere. Also try SuperAntiSpyware, it has very good detection, and its free. Scan your computer with the products, if still nothing is found, then try running your computer in Safe Mode (keep pressing F8 when your computer is starting) and run a scan, note that this will take many hours. Also make sure that you do full scans and not quick ones. If it still finds nothing, then get HijackThis! from TrendMicro, run a scan, and post the log on their forums, the users there can provide more help with that. If your problem still isn't solved, then there is a big chance that you have a rootkit, the worst, and hardest to detect type of malware. Try some free Anti-Rootkits.