I can run Fatty but not Blogbomb?

Ok I installed fatty no problem, but trying to install bbxrss2 just isn't working. I've done it before and cannot figure out why I am getting this error! My host told me it was something to do with the uppercase/lowercase so I made all my cases lower, and I still get the error...even tryed changing ALL permissions to 777 lol and nothin.

Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request. Contact Admin blablablahh

Any advice?