Getting 404 error on MVC web-site

Question

I have an IIS7.5 web-site, on Windows Server 2008, with an ASP.NET MVC2 web-site deployed to it. The website was built in Visual Studio 2008, targeting .NET 3.5, and IIS 5.1

Answer 1

We finally nailed this issue by exporting the IIS configuration of a working server, and comparing it to ours.

It was a really obscure setting which had been changed from the default.

IIS ROOT → request Filtering → Filename Extensions Tab → Edit Feature Settings → Allow unlisted file name extensions

This should be ticked.

This can be set at the IIS level, or the site-level.