How to Remove Happy99.exe (ska)

This type of worm are attached to newsgroups and e-mail messages as attachments and are usually known as Happy99.exe. Fortunately you will not get infected by this malicious program just by reading a mail. Just like any other virus this program needs to be executed to be able to infect your PC or spreads itself.  If you notice this on your mail don’t blame the sender of the mail with a happy99 attachment generally they do not know that they sent a mail with a happy99.exe worm just delete it and move on. If you execute an infected attachment, it will display a firework display, once its been activated every email you send will have the file attached. When someone else opens it, the virus spreads and the destruction continues.

These are the steps you can follow to remove Happy99.exe

Steps marked optional are not absolutely necessary and are completely safe to skip. If you’re not comfortable with DOS, get someone knowledgeable to help you with this. I cannot make guarantees of perfect safety since its a manual removal, Perform these at your own risk. If you have Windows NT, you don’t have to follow the removal steps.

1. Click Start, then Shut Down, then “Restart Computer in MS-DOS mode”, then click Yes. It’s important to exit Windows in order to be able to replace the file WSOCK32.DLL which Windows normally has in use.

2.At the DOS prompt type this exactly and press enter at the end of each line:


3. Delete SKA.EXE and SKA.DLL by typing


If you get “File not found” you’re either not infected or in the wrong directory. Make sure you’re in your Windows System directory; check to see if you followed step 2 exactly.

4.Copy WSOCK32.SKA to WSOCK32.DLL by typing


Answer “Yes” if it asks if you want to overwrite WSOCK32.DLL.

WSOCK32.SKA is a backup of the original WSOCK32.DLL. You are replacing the modified DLL with the original. If you get a “Sharing violation” make sure you followed step 1.

5.Optional Delete WSOCK32.SKA by typing


You can leave WSOCK32.SKA on your system. It is a copy of your original WSOCK32.DLL Do not delete WSOCK32.SKA if you are unable to replace WSOCK32.DLL with WSOCK32.SKA.

6.Return to Windows by typing


7.Optional Delete Windows Registry Key.
Click Start, then Run, then type regedit in the text box, then click OK. Click HKEY_LOCAL_MACHINE, then Software, then Microsoft, then Windows, then CurrentVersion. Under RunOnce check for SKA.EXE and select it if it is there. Press delete and then click Yes. Close Regedit. Don’t change anything else without making a backup of the registry first. If you don’t find SKA.EXE in the registry, it doesn’t mean you’re not infected. SKA.EXE is only added to the registry if HAPPY99.EXE is unable to modify WSOCK32.DLL when you run it. Also, you’ll only find it in the registry if you haven’t rebooted since you ran HAPPY99.EXE.

8.Optional Choose Start, Programs, Accessories, Notepad, choose File, then Open then type C:\WINDOWS\SYSTEM\LISTE.SKA in the File Name box. Warn the people on the list, then delete LISTE.SKA. Make it clear to the people you warn that they won’t be infected unless they ran happy99.exe, to avoid alarming them unnecessarily. If you haven’t sent out any infected e-mails, there won’t be a LISTE.SKA.

9. Optional Delete the HAPPY99.EXE file. The location of HAPPY99.EXE will vary depending on where you saved it. You can delete it simply by dragging it to the Recycle Bin from within Windows or whatever method you prefer. You may still have some messages with HAPPY99.EXE attached in your mailbox. These cannot do anything unless you run them. You can delete them if you want to or just ignore them. 10.Optional If you aren’t sure whether WSOCK32.DLL is infected, choose Start, then Find, then “Files or Folders”. Then type WSOCK32.DLL in the “Named” box. In the “Look in” box choose drive C: or whatever drive you have Windows on. In the “Containing Text” box type “ska.dll” without the quotes. Then click “Find Now”. If you don’t find any files, that means that wsock32.dll isn’t the modified version. If you don’t have the modified WSOCK32.DLL, the virus has no way to attach to e-mails, even if you have SKA.EXE, SKA.DLL, and WSOCK32.SKA in the Windows System folder. If you have SKA.EXE in the RunOnce registry section, and you haven’t deleted SKA.EXE, then the virus will try to modify WSOCK32.DLL the next time you restart the computer.

Make sure you type the instructions exactly including spaces and punctuation. You might want to print out the removal instructions so you have something to refer to. If you’re having trouble with the DOS commands, get a local person to help you with them. It’s hard to know exactly how you’re typing the DOS commands and what your exact situation is without seeing it in person.


  • Having a clean, locked, boot disk or CD on file helps with rescue and virus removal efforts.
  • Only modify the registry as explained in the steps above to avoid serious operational errors.
  • Locking a clean wsock32.dll file protects it from being modified by a virus in the future.