The following section explains how to see the true error message, rather than “Internal Server Error”. This is done by turning off friendly error messages in Internet Explorer. This is helpful when troubleshooting or developing your page so you can see the error messages your pages are creating in the browser when the page is viewed.
To turn off friendly error messages, please follow these steps:
Open Internet Explorer.
From the Tools menu, select Internet Options.
Click the Advanced Tab.
Scroll down until you see a checkbox labeled Show friendly HTTP error messages. Uncheck this box.
Click Ok.
Reload your page. Depending on your browser it may be necessary to close the browser, reopen it and attempt to load your page again.
You should now see a more detailed error message which should allow you to troubleshoot the issue you are having.