1. Symantec/
  2. Security Response/
  3. Happy99.Worm


Risk Level 2: Low

January 27, 1999
February 13, 2007 11:35:50 AM
Also Known As:
Trojan.Happy99, I-Worm.Happy, W32.Ska, Happy00
Systems Affected:
Windows 3.x, Windows 95, Windows 98, Windows Me
CVE References:

When executed, the infected program opens a window entitled "Happy New Year 1999 !!" and shows a fireworks display to disguise its installation. This worm sends itself to other users when the infected computer is online.

The following error messages can be symptoms of Happy99.Worm:

"MSIMN caused an invalid page fault in module Kernel32.dll"
"MSIMN caused an invalid page fault in module unknown"
"Explorer caused an invalid page fault in module Mailnews.dll at 014f:62060a0f"
"Outlook caused an Invalid Page Fault in module Unknown"
"MSIMN caused an invalid page fault in module Inetcomm.dll"

For additional information on these errors, see the Microsoft Knowledge Base article OLEXP: Error Message: "Invalid Page Fault in Kernel32.dll" with Happy99.exe Virus, Article ID: Q221486

Antivirus Protection Dates

  • Initial Rapid Release version January 28, 1999
  • Latest Rapid Release version August 8, 2016 revision 023
  • Initial Daily Certified version January 28, 1999
  • Latest Daily Certified version August 9, 2016 revision 001
  • Initial Weekly Certified release date January 28, 1999
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.
Writeup By: Raul Elnitiarta

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