No, this isn't the usual file format problem. I have an issue with CS6 where sometimes the program gets into a "locked state" where going into File > Open, Open Recent >, double-clicking, dragging into the app menu etc etc results in no action. No error is thrown, the program simply does nothing.
Now, locked isn't the right word, because I actually continue to work on any open documents, use tools etc. I just simply can't open any new files through any of the various ways you can open files. And, like I said, it returns no errors after I attempt to open something new. I can hit File > Open > Browse to my desired file > click it > click open, and the dialogue box closes like it would before opening a file – but nothing happens.
I've tried all sorts of cures, but nothing fixes this and I can't tell what's causing it to start happen. The only fix is closing out Illustrator and restarting.
Version 16.0.1 of Adobe Illustrator CS6
iMac
27-inch, Mid 2011
Processor 2.7 GHz Intel Core i5
Memory 16 GB 1333 MHz DDR3
Graphics AMD Radeon HD 6770M 512 MB
Software Mac OS X Lion 10.7.5 (11G63)