The Winkiller.A trojan was spread mostly through E-Groups and a few other discussion lists as a file called X1.exe. The program once it is executed prevents the computer from booting again by replacing critical Microsoft Windows files with its own files and editing the Win.ini file and disabling it.

After the damage is done, it displays a "Readme" box with the following text:

AS YOU MAY NOT KNOT. YOU ARE INFECTED WITH
X1 VIRUS. YOUR COMPUTER AND FILES WILL BE
SPARED AS LONG AS YOU DON'T RESTART YOUR
COMPUTER!! TO OBTAIN A CURE, SEND A MESSAGE TO
THE FOLLOWING ADDRESS:

eminemsux11211@hotmail.com

THANK YOU.
YOUR REQUEST WILL BE ANSWERED SHORTLY.

What Files are Replaced or Deleted?

Winkiller replaces the following critical Windows files with a copy of its file:

\windows\winsock.dll
\windows\win.com
\windows\wininit.exe
\windows\system\dllhost.exe

It also disables the WIN.INI file by adding comments (;) in front of most commands, and reduces the size of the file to 1K.

How to Clean/Delete the Winkiller trojan?

If you noticed that the size of win.com in your computer is reduced to 1Kb and you detect this Trojan in your system, please do the following:

(Don't Reboot Your Computer Before Completing These Instructions)

1. Replace the following files with a clean ones from a clean computer
   
   \windows\Winsock.dll
   \windows\Win.com
   \windows\Wininit.exe
   \windows\system\dllhost.exe
   
2. Click START, RUN
   Type WIN.INI and hit the ENTER key.
3. Delete all the comments( ; ) at the start of each line of WIN.INI.
4. Save the changes made to win.ini.

Now update your anti-virus program and scan for the virus.