Dots in URL causes 404 with ASP.NET mvc and IIS

After some poking around I found that relaxedUrlToFileSystemMapping did not work at all for me, what worked in my case was setting RAMMFAR to true, the same is valid for (.net 4.0 + mvc3) and (.net 4.5 + mvc4).

<system.webserver>
    <modules runAllManagedModulesForAllRequests="true">

Be aware when setting RAMMFAR true Hanselman post about RAMMFAR and performance

I got this working by editing my site's HTTP handlers. For my needs this works well and resolves my issue.

I simply added a new HTTP handler that looks for specific path criteria. If the request matches it is correctly sent to .NET for processing. I'm much happier with this solution that the URLRewrite hack or enabling RAMMFAR.

For example to have .NET process the URL www.example.com/people/michael.phelps add the following line to your site's web.config within the system.webServer / handlers element:

<add name="ApiURIs-ISAPI-Integrated-4.0"
     path="/people/*"
     verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS"
     type="System.Web.Handlers.TransferRequestHandler"
     preCondition="integratedMode,runtimeVersionv4.0" />

Edit

There are other posts suggesting that the solution to this issue is RAMMFAR or RunAllManagedModulesForAllRequests. Enabling this option will enable all managed modules for all requests. That means static files such as images, PDFs and everything else will be processed by .NET when they don't need to be. This options is best left off unless you have a specific case for it.