A faulty signature update from Kaspersky Lab on Wednesday flagged up Windows Explorer (explorer.exe) as infected with a low-risk virus, Huhk-C. As a result the core Windows component was quarantined or worse.
Kaspersky released a revised update alongside advice on how to recover legitimate system and application files from quarantine (the default setting) within two hours. But that’s not much consolation for users that had set their software to auto-delete infected files, who found themselves with hosed systems.
Among those affected was Reg reader Carl. “A false positive caused the deletion of explorer.exe.,” he reports. “It would have only caused problems for companies performing their network scan during the hours that the dodgy update was present – which included me, unfortunately. I was working out of hours to fix the previous Kaspersky update problem. I finally finished sorting it all at 5am.”.