When playing Skyrim I can receive messages via Steam just fine (in the bottom right of my screen) but I can't use my shortcut to open the overlay.
I have always had my shortcut changed from Shift+Tab to PAUSE|BREAK but changing the shortcut back makes no difference.
How can I fix this?
Google has helped me find people with similar problems but no answers, so I thought I'd be the first to post this problem on these official forums (because I can't find anyone here with my problem).

I'd appreciate any input on the matter.

Running on windows through Steam.