Registering an HttpHandler in IIS 7 Running in Classic Mode

We use quite a few HttpHandlers in the Haulix codebase. If you are running in IIS 7 Integrated Pipeline Mode, then registering your handler is trivial. In the web.config file, find the system.webServer node and add a line to the handlers section.

<handlers>
      <add name="SampleHandler" verb="*"
        path="SampleHandler.new"
        type="SampleHandler, SampleHandlerAssembly"
        resourceType="Unspecified" />
    </handlers>

I had a situation in a different website where I was running in IIS 7 Classic Mode. Registering a handler requires a few more steps. Most of the HttpHandler articles I found online referenced using the .ashx extension and the WebHandler directive, which can be called directly without having to setup the web.config or IIS file extension mappings. So, I hope this will help others who have had a hard time finding the solution. For this to work, you have to define both an httpHandlers element AND a handlers element in the web.config.  The lines in red are important and are what threw me off the first time.

<configuration>
  <system.web>
    <httpHandlers>
      <add verb="*" path="SampleHandler.new"
        type="SampleHandler, SampleHandlerAssembly" />
    </httpHandlers>
  </system.web>
  <system.webServer>
      <add name=SampleHandler" verb="*" path="SampleHandler.new"
      Modules="IsapiModule"
      scriptProcessor="C:Windows\Microsoft.NET\Framework\v2.0.50727\aspnet_isapi.dll"
      resourceType="File" />
  </system.webServer>
</configuration>