The various OPC specifications state how an OPC Server should communicate with an OPC Client. However, the OPC specifications do not state how each product should be configured. To find out how to configure a specific OPC application (such as an OPC Server or a Client application), you must consult the specific product documentation.
There are many reasons an OPC Client application will fail to connect to an OPC Server. The single most common reason is a failure to pass the Windows authentication process. The OPC Training Institute’s website covers many of these reasons in detail. Our whitepapers (available for free) list various error conditions, their causes, and how to solve them using a step-by-step guide.