I use a Mac, OS X 10.9.5 and have a subscription to Creative Cloud.
I have wasted pretty much my whole afternoon and evening trying to sort this but to no avail - and, yes, I have read other posts, the same issues, etc.
I was using the Camera Raw function in Bridge CC fine. Then I went to use it again and it's greyed out and can't be opened. I have restarted my Mac, opened and closed Bridge and Photoshop and tried some of the suggestions on other forums but it still won't illuminate/work.
I am convinced iPhoto is the issue as I was trying to get photos from iPhoto to Bridge (not entirely successfully or without some choice language) and it was in the midst of that process that it seemingly stopped working, but maybe a coincidence.