You probably also want to check your computer date and time.
Right click the clock in the system tray. Select Adjust Date and Time.
Verify and correct the month, day, year, hour, minutes and time zone.
Reboot if you changed any of the above.
If that does not resolve the issue, please open a support case.
To open an email support case, start here:
https://support.microsoftsecurityessentials.com/
-steve
~ Microsoft MVP Windows Live ~ Windows Live OneCare| Live Mesh|MS Security Essentials Forums Moderator ~