UI_AdminRequiredNotice

Has anyone else seen this error? If so, how did you get around it?

I get this in SL2 when I open the program. Once I click close, it tells me my free trial is up and that I can activate with my serial number. When I do that, it tells me my serial number is invalid, which it's not.

Note: I updated from Windows 8 to 8.1 over the weekend. Thanks, everyone!