Here are the most dangerous viruses I have encountered

Here are the list of virus I have found by the Avira and Avast!:

• Sality (Program infecting and modifier.)
• Palevo (Disable the format function and the Folder Option of the C.P.)
• Hakaglan (Spool drainer of Epson printer LX-300 series.)
• Frethog (Password Stealer.)
• VB-Nik (Disable the loading operation of Power DVD and the Macromedia flash player.)
• Flot (JPEG file damager.)
• Rootkit-gen and Confi (Autorun.inf modifier and loader.)

Undetected Virus

Antivirus Avira Personal version 10.0.0.596 found the TR/Drop.Agent.cxem Trojan on the program files and system volume information (hidden folder) directory. This trojan cannot detected by the MS Security Essentials version 1.0.2498.0 even you change mode to FULL scan.

Viruses Found on my PC

BEWARE!!! these viruses like Backdoor:Win32/FlyAgent.F, TrojanClicker:Win32/Yabector.B, Worm:Win32/Rimecud.B, Trojan:Win32/FlyStudio.G!inf, Virtool:Win32/DelfInject.gen!BE and Trojan:Win32/Starpage.gen!A are residing in hidden system volume information of your Windows XP SP2 & SP3, found by the "Microsoft Security Essentials".