title: WinCC OPC UA authenticationproblem
body: <p>I'm trying to connect a Simatic S7-1500 PLC to a WinCC SCADA system by OPC UA. The OPC UA server is KEPServerEX. I cannot get an OPC UA connection done between KEPServerEX (server) and WinCC explorer V7.3 (cliënt) with authentication enabled. I configured identification in user manager of KEPServerEX. I have encryption/signing security not enabled. I can browse the server in WinCC (with a wrong authentication I can't, so the username and password are correct), I can select tags, but when I add this server in tag managment, the connection status is and stays disconnected + I get the error: 'Error while ValidateItems: Unspecified error (80004005)'. Wireshark gave me a message called ServiceFault (BadUserAccessDenied). Also when browse is configured as denied in user manager, I can't browse in WinCC in task manager (as it should be).</p>
  
  <p>I tried UAExpert as cliënt (just for testing purposes) to connect to the KEPServerEX OPC UA server, and this gave me a ''BadSecurityModeInsufficient' during ActivateSession' Error (if sign&amp;encryption is disabled). If got the error ''BadVertificateHostNameInvalid' during CreateSession' (if sign&amp;encryption is enabled) When I click Ignore, it works in both cases. But I want to get a connection with WinCC. Is there something I did wrong?</p>
  
  <p>Thanks in advance,</p>
  
  <p>Roel Konings</p>
  
  <p>EDIT:</p>
  
  <p>This is what I get in wireshark when I got a connection with WinCC:
  <a href="https://i.stack.imgur.com/OUkbT.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/OUkbT.png" alt="enter image description here"></a></p>
  
  <p>It is just in a loop with Hello/Acknowledge, opensecurechannel, getendpoint and closesecurechannel, but there is no real connection. Someone who can help me with this? It only happens when authentication is enabled.</p>