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TeamViewer 9 fails to connect with error: "No connection to TeamViewer server"


Article ID: 173270


Updated On:


ProxySG Software - SGOS


  • TeamViewer 9 is configured to make an explicit connection to the ProxySG.
  • Upon connection attempt, the application displays the error: "No connection to TeamViewer server"

No connection to TeamViewer server


  • TeamViewer 9 uses the CONNECT protocol with non-TLS compliant SSL.
  • In a policy trace, you will see the proxy generates the error "EXCEPTION(connect_method_denied): CONNECT with a protocol other than SSL is not permitted"


We need to add CPL code to tell the proxy to allow the CONNECT requests which are using non-TLS compliant SSL. We need both rules because TeamViewer 9 will make CONNECT requests to * domains and to IP addresses.

http.method=CONNECT ALLOW
http.method=CONNECT request.header.user-agent=DynGate ALLOW