What a mess, it turns out a particular virus definition update from McAfee has caused some major headaches today for systems running Windows XP. The 5958 virus definition update is breaking Windows XP by removing a critical system file, causing the McAfee anti-virus software to freak out and force restart the computer. The computer then becomes inoperable without networking functionality and a constant loop of restarts. To make matters worse, because of the huge influx of traffic their support forums are down.

McAfee has already pulled the update from their servers, but not before breaking Windows XP systems from all over the world. Nobody knows how many computers were affected, but according to Engadget the total may reach into the millions. The unfortunate thing is that there is no easy way to roll out a fix, the only way to correct the problem is by following McAfee’s workaround. This could be a devastating amount of work for IT admins who have to hand fix thousands of computers.

A good backup system could go a long way too I suppose, but you still have to wonder how this update slipped past McAfee. You would think that all updates are tested on every OS they support. Maybe because Windows XP is older they messed up somehow. The only question is, how will they prevent more updates from breaking Windows XP systems? Anti-virus is supposed to protect against software specifically written to cripple computers, but nobody could have guessed that an update would cause so many problems.