Diagnosing and fixing Remote Viewer connection problems

Diagnosing and fixing Remote Viewer connection problems

Remote Viewer connection issues are often due to one of the following:
  1. The Remote Viewer is not enabled in the Engine's configuration
  2. The Engine is stuck in Startup and not yet listening (v6.35 and earlier)
  3. The Engine is unable to listen on the configured port
  4. The Remote Viewer is being blocked by a firewall
  5. The Engine has already reached its licensed Remote Viewer connection limit

Verify that the Remote Viewer is enabled in the Engine's configuration

  1. Run the Configurator and open the configuration file for the Engine
  2. Select "Remote Viewer & Dial-in" from the left menu
  3. Make sure that "Enable remote access from the TopView Remote Viewer" is checked

Verify the the Engine is not in the Startup state (v6.35 and earlier)

In TopView v6.35 and earlier, the Engine does not start listening for Remote Viewer connections until it is in the Running state.

Verify that the Engine is listening on the configured port

In Admin Tools, click the "Remote Viewer Connections" link in the left menu.
"Listening" must be True on the "Selected TopView Configuration" tab.
  1. If listening is False and the Engine is not in the Startup state (v6.35 and earlier), the configured port may already be in use by another TopView Engine or another application. 
    1. Select "Application Log" from the left menu of Admin Tools
      1. If the Engine was not started or restarted today, select the daily application log file for the day that the Engine was last started or restarted
      2. In the "Message containing text" box enter
        Remote Viewer
      3. Click the [Refresh] button
      4. Look for messages similar to "error setting up socket for listening.... only one usage permitted"
      5. If you see this message you need to select a different listen port in the Engine's configuration
  2. If listening is True
    1. Run the Remote Viewer on the TopView machine to see if you can connect
    2. If you can connect but remote users are unable to connect, the issue is most likely due to a firewall
    3. The firewall could be on the TopView server or client-side. Ensure communication over the specified port is allowed on both systems. 
To test whether the client can connect to the Remote Viewer port, use either of the following methods:
  1. telnet to the port from the client machine:
    1. Run the following in a command prompt with access to telnet with the hostname/IP and Remote Viewer port on the TopView server: telnet <host> <port>
  2. Use Powershell's "Test-NetConnection" command from the client machine:
    1. test-netconnection <host> -p <port>

Verify connection is within the licensed connection limit

The TopView engine is licensed for a certain number of connections. If existing Remote Viewer connections have taken up all licensed connections, then subsequent Remote Viewer clients will fail to connect to the TopView engine.

You can see how many connections are currently in use in the TopView Admin Tools application. Look for the "Remote Viewer Connections" link in the left sidebar.

Ensure you have the engine you want to inspect selected in the top drop-down bar of the application, Then, in the "Selected TopView Engine" tab you will see a list of connected Remote Viewer applications, along with identifying details.

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