Bad McAfee virus definition update causes PCs around the world to crash

A bad update for McAfee security software has caused Windows XP computers around the world to shut down and restart continuously.

Virus definition update 5958, issued at 6 a.m. Pacific time, caused McAfee software to incorrectly identify the Windows system file svchost.exe as an infected file — W32/wecorl.a.

The software then deletes svchost.exe on computers running Windows XP Service Pack 3, causing many key Windows services to fail, Ars Technica wrote.

The bad update was removed and the company issued a fix, PC Magazine reported. McAfee offered these fixes.

Someone here in the newsroom said that she’d heard from a friend working at Montana State University that the McAfee bug had caused some trouble for the campus. Indeed, the university offers students and staff copies of McAfee software to secure their machines.

I have left a voicemail at MSU’s IT department asking how bad the disruption was. I’ll pass on word when I know more.