Strange MSE behavior.

Today I've had Microsoft Security Essentials stop in the middle of scan, shut itself completely off (not in taskbar, not in task manager). I was alerted to this by the security center, which told me I had no malware protection at all. Just as I was starting to go into panic mode, a few minutes later MSE restarted itself without completing the original scan or having any record of starting the original scan.

The security center gave me this readout, with the strange stock icons.

I started scan again, and MSE shut itself down in the same way. I restarted computer and the scan function seemed to be working again, but the icons in the security center were still stock.

MSE was automatically updated yesterday so definitions should be up to date. I ran another scan with malwarebytes and SS&D with no abnormal results (a few tracking cookies).

Am I being paranoid or is something wrong with MSE?

 

I see from the screen capture you're running Vista or later. I haven't switched back to Vista from XP today yet, so I haven't updated MSE in Vista. But, while running XP, Windows Update came up in the System Tray with an update to the MSE app. Once it was updated, a nag screen about the end of support for XP came up and it comes up every time I boot into XP AND the System Tray icon is orange with a white exclamation mark in it, I don't know if the MSE update in XP also affected MSE in other versions of Windows.

You can go to Start and type in "eventvwr" (without the quotes) and see if/what it reports. If there was a problem with MSE, you can uninstall and reinstall it along with the definition updates.

As for me. I'm redoing my XP drive without MSE. I'm going to run Comodo Internet Security Premium. SuperAntiSpyware and Spyware Blaster.

 

I had problems with the latest version of MSE on XP. The tray icon stayed orange because it wants me to know XP support is ending but additionally the Red Shield of Security Center popped up and told me I had no antivirus installed! Apparently the OS no longer recognizes the latest version of MSE in XP.
I uninstalled it (I used Revo Uninstaller) and reinstalled the previous version.