Keying set failed to insert any keyframes When pressing I, I now receive: 


  keying set failed to insert any keyframes.


No idea why pressing I doesn't work anymore. What did I do wrong?
(I've upgraded from 2.71 to 2.72 and it stops working).
See screenshot: The solution was to remove the keying set at the bottom and when selecting the camera, to remove the 2 keying sets that were there.

I however have no idea how this was enabled, and at this point of time I also don't know the goal of this keying. 

After removal, the I key worked again.