Earlier on Friday Microsoft issued an update to its Microsoft Security Essentials anti-virus program. The definition update seemed to have deleted Google’s Chrome web browser from users machines.
Chrome users began reporting the specious detection of the browser early Friday in a quickly-growing thread on a Google support forum.
“This morning, after I started up the PC, a Windows Security box popped up and said I had a Security Problem that needed to be removed,” said someone identified as “chasd harris” in the first message of the thread. “I clicked the Details button and saw that it was ‘PWS:Win32/Zbot.’ I clicked the Remove button and restarted my PC. Now I do not have Chrome. It has been removed or uninstalled.”
Scores of others reported the same behavior on their Windows PCs running Microsoft’s Security Essentials — its free, consumer-grade antivirus software — as well as Forefront, the antivirus product designed for enterprises.
Microsoft issued another update about 3 hours after the first went live which fixed the issue, but said that about 3,000 users were effected.
This is no where near the first or worst instance of anti-virus vendors issuing bad updates. More than a year ago McAfee issued an update that deleted critical Windows XP system files that wreaked havoc of corporate systems.
This is not too common of a problem, but anti-virus vendors must be fast in responding and fixing issues people have before they create too much damage. Speed is the name of the game for anti-virus vendors, in responding to new attacks and fixing issues customers have with their software that break there systems.