500 Server Error

i have 20 mis left to upload! please dont take these a and c 2 from me I finally completed them and now this........

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

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

Error: httpd: malformed header from script