I was trying to punch up some "Doctor Who" while I exercise today (08 Jan 2014).
I guess it's no longer alright to have your computer set to the correct date.
DRM sucks. Just sayin'...
The fix... Looks like a Silverlight file called mspr.hds somehow got corrupt. All I had to do was delete it from:
... and I'm back in business.
(Did I mention DRM sucks? Necessary evil for streaming content, I know, but still...)