IIS gives 404 when MS-DOS reserved names are used in parameters values

Question

I have an ASP.NET Web API application and I have an action that takes one string parameter, such as:

[HttpGet]
public HttpResponseMessage GetById(string id)
{
    // ...
}

It is registered accordingly:

config.Routes.MapHttpRoute("Resources", "api/resources/{id}", new
    {
        controller = "Resources",
        action = "GetById"
    });

Now, when someone calls api/resources/con, IIS gives 404. Almost any other value is OK, like api/resources/something or api/resources/nothing.

We have looked over and found that none of the reserved MS-DOS Device Driver Names can be used as a parameter value.

This appears to be a global issue, since MSDN has it too:

• http://msdn.microsoft.com/con
• http://msdn.microsoft.com/prn
• http://msdn.microsoft.com/nul

Is there any way to allow these names to be used as route parameters values?

Answer 1

Add this in Web.config, under system.web.

<httpRuntime relaxedUrlToFileSystemMapping="true" />