Failed WebX Client or XML Client - System Connections

If you attempt to access your system from a WebX, Original WebX or XML client and it is unable to establish a connection, the web browser application that you are using will display a ‘connection failed’ message.

WebX uses IIS web services to connect to connect to the ClearSCADA Server. When you install ClearSCADA the IIS web services are automatically configured with default settings to allow WebX clients to connect to the server, see Web and Mobile Setup.

Original WebX and XML clients use the built-in Web Server to connect to the ClearSCADA Server. The settings for the Web Server are configured using the System Configuration Tool, see Web Server Settings.

If your web browser displays a connection failed message, it may be because:

• The user of the WebX, Original WebX or XML client has entered an incorrect port number in the Address field on the browser (if the default ports are not used).
• The network connection between the client PC and server PC is unavailable. This may be due to failed hardware or a temporary loss of connection. If you suspect that there is no network connection, please contact your network administrator.
• There is a firewall blocking the connection between the client PC and the server PC. If a firewall is being used between a WebX, Original WebX or XML client and the web server, you need to configure it to allow the ports that are being used. For more information on configuring your firewall, please refer to the manufacturers’ documentation supplied with the firewall software or hardware.

  The default settings for WebX within IIS web services are (http) 85 and (https) 453.

  NOTE: When you upgrade your ClearSCADA installation the IIS web services settings are set to the default values unless you change them during the installation process, see Web and Mobile Setup.

  The default settings for Original WebX and XML clients with the Web Server are (http) 80 and (https) 443.

• The configuration that enables the Original WebX and XML client to communicate with ClearSCADA via a proxy server or proxy firewall is incomplete or incorrect. For example, the proxy settings in ClearSCADA differ to those configured in the proxy application in which the actual port mapping occurs, or the mapping is configured incorrectly in that application. (This scenario only applies if your system uses a proxy server or proxy firewall between the WebX server and Original WebX clients, and the Original WebX clients are set up to communicate with ClearSCADA via the proxy.)
• A third-party web server on the ClearSCADA server is using the ports that the ClearSCADA web server is configured to use. For example, if the Apache web server is installed on the ClearSCADA server and is using port 80, it will stop the ClearSCADA web server from using port 80. In this situation, there are two possible solutions:
  • You can reconfigure the ClearSCADA server so that the ClearSCADA web server uses different ports for the connection with WebX clients

    Or

  • You can reconfigure the third-party web server to use different ports.