title: Could not create SSL/TLS secure channel - Could the problem be a proxy server?
body: <p>I have a c# app that calls a web service method that authenticates using a certificate. 
  The code works, because when it is installed on server A (without a proxy) it authenticates. </p>
  
  <p>When I install the code on server B, at client site, its installed behind a proxy. I've really tried almost everything but I keep getting this error:</p>
  
  <p>Could not create SSL/TLS secure channel</p>
  
  <p>Do you think this issue can be caused by a proxy server? If you've had any personal experience with this please share. </p>
  
  <p>Thanks</p>