|Troj/SdBot-BI is an IRC backdoor Trojan which allows unauthorised access and control of the computer from IRC channels.
Also known as Backdoor.SdBot.kd, W32/Spybot.worm.gen.b, Win32/SpyBot.WW, Backdoor.IRC.Bot
Upon execution Troj/SdBot-BI displays the fake error message
"'Error-38427 A valid dll file was not found, Windows is now deleting file."
In order to run automatically when Windows starts up the Trojan copies itself to the file:
mmsnmessengerupdate.exe in the Windows system folder,
and adds the following registry entry to ensure it is started on computer logon:
HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\svshostdriver = msnmessengerupdate.exe
You can easy remove it with antivirus (also check How To Remove section)