The remote server returned an error: (403) Forbidden

Question

I\'ve written an app that has worked fine for months, in the last few days I\'ve been getting the error below on the installed version only.

If I run the source code

Answer 1

In my case I remembered that a hole in the firewall was created for this address some time ago, so I had to set useDefaultWebProxy="false" on the binding in the config file, as if the default was to use the proxy if useDefaultWebProxy is not specified.