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Error when subscribing to A&E server

19 Aug 2020 06:53 - 19 Aug 2020 06:54 #8778 by support

QuickOPC does not currently support COM-based OPC specifications under .NET Core. Check footnote (4) here: .

Note: You are using a pre-release version of the software - please do not use them, unless instructed to do so. They are for our internal use only, are not supported and sometimes may be far from functional.

Best ragards
Last edit: 19 Aug 2020 06:54 by support.

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18 Aug 2020 19:47 - 19 Aug 2020 06:48 #8777 by ScottEwine
I took a snippet of your code from the website and put it into a simple 'hello world' app to test it out. This is a console application with a .NET core 3.1 target using Visual Studio 2019. I am using QuickOPC 5.59.0-rev13. The full code is at the bottom of the post.

When I run the application I get this:

*** Failure: The requested OPC Alarms&Events technology 'Com' is not supported. Check the scheme "opcda" in server URL string "opcda:Matrikon.OPC.Simulation.1".

Note that I am trying to connect for A&E information, but it is appending "opcda:" to the beginning of the connection string that it returns. I get the same error when I use the OPCLabs event server.

using System;
using System.Diagnostics;
using System.Threading;
using OpcLabs.EasyOpc;
using OpcLabs.EasyOpc.AlarmsAndEvents;
using OpcLabs.EasyOpc.AlarmsAndEvents.OperationModel;
using OpcLabs.EasyOpc.DataAccess;
using OpcLabs.EasyOpc.OperationModel;
namespace ConsoleApp1
    class Program
        static void Main(string[] args)
            Console.WriteLine("Hello World!");
        public static void Main1()
            using (var client = new EasyAEClient())
                var eventHandler = new EasyAENotificationEventHandler(client_Notification);
                client.Notification += eventHandler;
                //int handle = client.SubscribeEvents("", "OPCLabs.KitEventServer.2", 1000);
                int handle = client.SubscribeEvents("", "Matrikon.OPC.Simulation.1", 1000);
                Console.WriteLine("Processing event notifications for 1 minute...");
                Thread.Sleep(60 * 1000);
        // Notification event handler
        static void client_Notification(object sender, EasyAENotificationEventArgs e)
            if (!e.Succeeded)
                Console.WriteLine("*** Failure: {0}", e.ErrorMessageBrief);
            if (e.EventData != null)
Last edit: 19 Aug 2020 06:48 by support. Reason: code formatting

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