I have a problem with an ASP.NET MVC site.
These are the details:
I had the same problem when I installed IIS after installing Visual Studio, etc.
I was able to fix the problem by changing my Web.config file, adding the runAllManagedModulesForAllRequests="true"
to the
tag:
...
(More details/copied from here: http://www.west-wind.com/weblog/posts/2011/Mar/27/ASPNET-Routing-not-working-on-IIS-70)