Content Editor is not loading.. System.InvalidOperationException: Could resolve language

 I am getting this error when I try to load content editor.

http://www.screencast.com/t/CONVT0SOupmz

But I am able to do other activities like package creation/installation through content editor.

http://www.screencast.com/t/jCs8m9UmAAm

I could I have no clue on how to resolve this. 

 

Can anyone give idea on resolving this?