500 Internal server error after re uploading DB and content.

Hi, my website got hacked so I deleted everything, restored the DB and uploaded the files again on a fresh copy of WP.

Now when I try to view or preview any of my pages i get this:
Internal Server Error

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

Please contact the server administrator, [email protected] and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

Additionally, a 500 Internal Server Error error was encountered while trying to use an ErrorDocument to handle the request.

I have a custom permalinks structure which seems to have caused a lot of problems for people in the past. Have looked into the other how tos on the permalinks and its still not working.

I havent installed any of the plugins that I had before yet. Could the DB be creating a problem because it is looking for a plugin that isnt there or something similar?

Thanks