"The server encountered an internal error..."

[Connie]

In my case the problem was related to the .htaccess file. The server produces error 500 if there is anything written into the htaccess.

So there are certain restrictions for .htaccess at your server. When you found out more about that, got information from your hoster, it would be great if you could add that info to our WIKI, as we collect "hoster specialities" there ...

In my eyes it is ridiculous to allow .htaccess but deny functionality for that file ;=(