Error Message For MultiSite on GoDaddy Server

I'm using a GoDaddy server for my multi-site installation of WordPress and I keep getting this message:

Internal Server Error

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

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

And when I create new sub-domain sites, the css seems to have a problem as I can see all the links but the theme does not show up.

Any help is welcome.