The 500 status message just means 'something went wrong on the server'. You will need to find a more specific error message. If nothing more is displayed in the browser, go into your IE Advanced Options and make sure that 'Friendly HTTP Errors' are NOT enabled (they hide the most useful information). If, after doing that, you don't see anything more informative, have a look in the server's Event Log (Application Log), and see if anything is recorded there.