Solving error: The remote server returned an error: NotFound

I had a weird issue today. I am calling an external website using WebClient inside my WCF application, and I consistently got this error in WebClient call: "The remote server returned an error: NotFound". The error did not give me enough clues. To debug it, I ran fiddler and to my surprise, the error doesn't happen when running fiddler. The error occurs only when not running fiddler.

Did a web search and suprised that no one seem to have hit it before. So writing this post. I asked my colleague Gopal Srinivasa and he immediately pointed out that we are behind proxy and we need to install Firewall Client/web proxy and it immediately solved the issue!

Comments (1)

  1. Tung Nguyen Thanh says:

    Hi Naren,

    I'm using Silverlight 4 with WCF RIA Service and I've face this problem many times but I don't know how to resolve it.

    If you have any suggestion for me. Please help me.

    My mail:


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