Yesterday my sis's com was infected with trojan. Eeew. Her desktop has changed to a blue background and Of cos, her special IT support (me) has resolved it for her. The trojan came with an anti-virus software imposter. There are many rogue software like this Antivirus XP 2008 [list]. Once installed, it will generate random files into your system and put up fake alerts informing that your system has been infected with virus.. many of them. The tactic is to scare the user into buying the fake product. Yes, it is kind of scary. How the hell did the computer manage to infect so many viruses in 1 click? Googled it and found Malwarebytes Anti-Malware on this website. It's pretty good and most importantly, it's FREE.
How we ended up with this crap?? Haiz.. here comes the moral of the story. There's no such thing as watching FREE movies, FREE Olympics online. DO NOT DOWNLOAD ANY SUSPICIOUS UNKNOWN PROGRAMS. My dad did a similar stupid thing earlier. He downloaded a player to watch free movies online. Killed some of his system files and explorer could not start up. With the help of my dad's ex-colleague, we found out that the problem is caused by some trojan and adware. Previous scans did not pick those up. The website suggested this 360 Safe software (chinese) but did not completely remove all infected files. There were still registry keys that were corrupted. Rechecked with Malwarebytes and got everything fixed.
If you're feeling geeky and have time, this website gives instructions on how to manually remove these counterfeit anti-spyware programs.