Locate your specific OPC Server from the list, right-click, and select .
// Your callback function void OnDataChanged(object subscriptionHandle, object requestHandle, ItemValueResult[] values) opcnetapidll
using Opc; using Opc.Da; // 1. Create the URL to the OPC Server URL url = new URL("opcda://localhost/Matrikon.OPC.Simulation.1"); // 2. Create the factory to manage the COM object Opc.Factory factory = new OpcCom.Factory(); // 3. Connect to the server SubscriptionState state = new SubscriptionState(); state.Name = "MySubscription"; state.Active = true; state.UpdateRate = 1000; // Create Subscription Subscription subscription = new Subscription(factory, url, state); Console.WriteLine("Connected to OPC Server"); Use code with caution. Troubleshooting Common OpcNetApi.dll Errors 1. OpcNetApi.dll Missing Locate your specific OPC Server from the list,