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UA Read Value Internal Error

24 Feb 2020 16:49 #8242 by support

I have some questions, in order to narrow the problem down:

1. What type is of project? (such as Windows Forms app, WPF app, console app, ASP.NET Web app, Windows Service, Web service etc.).
2. Which QuickOPC version are you using?
3. Are there other OPC operation in your program that work well - or is this basically the first you do in the program, and it fails.
4. When you open the solution with VB.NET examples delivered with QuickOPC and run them (such as the UADocExamples project), do they work or not?
5. Can you please modify the code to also show the .InnerException property of the exception object you are catching, and le tme know what the InnerException is?

Thank you

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24 Feb 2020 15:23 - 24 Feb 2020 16:44 #8241 by ncooley

I am using the following snippet of code;
            Dim attributeData As UAAttributeData
                attributeData = EasyUAClient1.Read(EndpointDescriptor, "nsu = http : // ;ns=3;s=[J37]Secondary_Codes[1]")
            Catch uaException As UAException
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException.Message)
                Exit Sub
            End Try

but I am getting a exception error;

System.TypeLoadException: 'Could not load type 'Opc.Ua.KeyValuePair' from assembly 'Opc.Ua.Core, Version=1.3.342.0, Culture=neutral, PublicKeyToken=6faddca41dacb409'.'

The tag syntax is correct and the Demo UA application reads the tag correctly.

Last edit: 24 Feb 2020 16:44 by support. Reason: code formatting

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