Few days’ back one funny issue came to me. All of a sudden on one of the Windows 2003 server my customer was getting “HTTP/1.1 500 Server Error” for any .asp pages in the application. It stopped working since last couple days and used to work earlier. So here the obvious question would be - What was changed two days ago?
Customer confirmed that nothing but the installation of Service Pack 2(SP2) of Windows 2003 was done.
This sounded funny to me but when I tested the universal Time.asp (script showing the current time using <%=now()%>) in the same application, interestingly even that gave “HTTP/1.1 500 Server Error” too! No extra filters nothing and still this behavior and I was confused.
I started thinking about this issue and checked the entire IIS pipeline which can interfere with the request – ISAPI, Extension mapping etc. but no luck. So the only thing which remains is the “Global.asa” which comes in the pipeline before the page execution starts. And bingo found an empty (0 KB) Global.asa in the application. Renaming it to Global.asa.old and everything worked.
So I tried this on my own test machine and got to conclusion that having empty (0 KB) Global.asa breaks the .asp page request execution after SP2 is installed on Windows 2003 Server and you will start getting “HTTP/1.1 500 Server Error”. Resolution to this would be not to leave this unwanted creature to live in the application 🙂
So if you have installed SP2 and simple test page is throwing an error “HTTP/1.1 500 Server Error”, make sure that you don’t have any Global.asa of 0 KB size in the application (possibilities are endless and it's one of them).
We do have a Knowledge Base article published for this - http://support.microsoft.com/default.aspx?scid=kb;EN-US;936476
I hope this help!