A recent Avira anti-virus update, downloaded by millions of users, effectively disabled users' Windows XP, Windows Vista and Windows 7 computers.

"The update bumps the software version to 8.2.10.64 and the definitions file to 7.11.30.24, writes ZDNet's Emil Protalinski. "The result is that the AntiVirProActiv component starts detecting critical processes as malware ... Avira sometimes kills them and stops Windows from booting, but that’s not the end of it. The update is also blocking other Microsoft software (such as Microsoft Office and Microsoft Works) as well as various third-party applications, including Byki 4 Express, Documents To Go, Garmin, Google Talk, iPod and Palm services, Opera, OpenDNS Updater, Polipo, Shadow, Stickies, and many others. In other words, almost every executable file is being falsely detected by this update."

"On the Avira forum, an employee of a company which runs Avira on one hundred computers complains that, 'This update has been pretty catastrophic. The whole company ground to a standstill,'" The H Security reports.


The company has since released an update that addresses the issue, stating, "We deeply regret any difficulties this has caused you. Thank you for your patience and understanding."

"The inadvertent blocking impacted Avira Professional Security, Avira Internet Security 2012 and Avira Antivirus Premium 2012, paid products priced between $30 and $60," writes Computerworld's Gregg Keizer. "Avira's free antivirus software, which has limited functionality -- and does not include ProActiv -- was not affected."