I have a precompiled MVC site which runs successfully on multiple servers, and on multiple sites within each server.
One particular site a few days ago suddenly stopped working, returning
HTTP Error 403.14 - Forbidden
I couldn't find anything that would cause it, and rebuilt the site using the same source code as other sites on the same server, in a different folder, and the site ran fine for about 24 hours before once again suddenly experiencing the same error.
There is nothing in the Windows logs (Win 2K12 Server) or in the IIS (6.2) logs (other than confirming the 403). This particular site is running on a Virtual Server in Azure, but plenty of other sites are too, including on the same virtual server using the same source code and settings (other than domain name bindings).
I've currently moved the binding to a different process which is working fine, but I really need to get to the bottom of this in case it suddenly happens again.
I've googled this for days without success. Turning on directory browsing works, but of course not something I can or want to permanently do with MVC. Both home and MVC route requests return the same result, but calls for specific files (eg, a text file in a sub-folder) are successful. That certainly suggests a MVC-specific issue. But I can't work out how to specifically isolate the issue.
Obviously I've reset the application pool, the site itself, and indeed set up a new site using the same application pool (which is working currently, but I'm worried it too will suddenly break at the worst time).
Does anyone have any pointers for working out the main cause, please?