Turn on Windows Security Services

hi......
1.open task manager and check that these two processes are up and running MsMpEng.exe and Msseces.exe
2. in action center-virus protection it should say on ...what does it say in your case?

those are applications, not processes. Use the next tab over, click show processes from all users. Set it to alphabetical order, scroll down to the M's and get a screenshot of that and post it. We will tell you if they are running or not.

EDIT: okay, never mind then.

Open the notification area customization page. Set the action center to notifications only. Then open action center. Click Change Action Center Settings. Turn off which ever one is causing the red x. I had to do this because it kept bugging me about my Windows Update settings.

hmmm......you can try the steps mentioned in the last post here Action Center shows Microsoft Security Essentials as turned off

Good link thathagat. Looks like both solutions there might help, assuming the latest updates for MSE aren't installed. If it works, its better than just turning off the warnings like I suggest.