Scan is deleting website login information in IE10
The Pro Active Threat protection and scans delete all login information (cookies) in IE10 when it finds a tracking cookie it wants to remove. It seem to clear all of them rather than just the threat.
It has been suggested that I recert back to IE9 untill this can be fixed, but I am running Windows 8 so I am not sure that is even possible.
See case Case #(04227279). for details.