The 500 Internal Server Error is a very general HTTP status code that means something has gone wrong on the web site's server but the server could not be more specific on what the exact problem is.
If you have access to the webserver, try looking at event logs/iis logs if it can give you more information.
Look at this link, it explains more about 500 Error Code:
http://pcsupport.about.com/od/findbyerrormessage/a/500servererror.htm[
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