WinFastener is a joke program/trojan on Microsoft Windows that never entered the wild, and was coded as a special release for one of the popular YouTuber Danooct1's videos. While it was created by a user, it was not added to the user-made malware as it was not made at the time.
When activated, it displays a message:
A32 Hello. This is A32. I just want to say that I really miss the times when viruses didnt slowly corrupt and take over your system, but instead banged you with a message that sayed your system is 0wned. Dont you just miss those times? [ OK ]
If the user clicks the OK button, the virus changes the message text to say "Your system is 0wnd", moves the message box in random positions, plays an MP3, being that of the Garry's Mod video What Happens when Louis gets his Pills, and deletes the critical file hal.dll (Hardware Abstraction Layer DLL), causing the computer to fail to boot when it is restarted.