Use Fiddler with .Net Application

I often need to watch communication between a web service and my application. The best way I’ve found is to configure my app to use Fiddler as a proxy between my application and the web service. Once configured, I can watch the traffic. The simple step that I keep forgetting is the entry in the Web.Config file.

Get Fiddler Settings

Open Fiddler and click on Tools -> Fiddler Options. The Fiddler Options window will pop up and take note of Listen Port number under Proxy Settings. In this case the value is 8888.

Fiddler Options

Update Web.Config

Open your Web.Config file and add the entry. Make sure the port on the address matches the one defined in Fiddler.

    <proxy  proxyaddress="" /> 

Other web referenced talk about setting other attributes on the proxy element, but don’t These seem to make it fail. Just the simple solution from Rick Strahl will make it work.