MT4 and MT5 losing all account data--"deleted due security reason"

For the third time this week I have rebooted my workstation and all of my MT4 and MT5 accounts have been blown away. I've had to re-enter account number, password, server, delete all EAs and download them again which counts as a new activation, etc., etc., etc. All of them say "Accounts deleted due security reason" in the Journal tab. At first I thought it was a Windows update or driver update that caused this, but today I only updated my nVidia driver and rebooted and it happened again. I have 6 accounts that this has happened to a few times this week. My laptop and VPS don't have this problem, only my workstation, but I've used it for over a year without this happening before this week. Any idea what's causing it or what that error means?