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EasyUAClient corrupts heap memory so that Dapper crashes

17 Jan 2022 08:49 #10544 by support
Dear Sir,

I suspect (although I am not sure) that I know the cause. It could be related to a 3rd party library that we use, and that commonly has issues when newer versions of operating system are released. We then included a newer version of the library in newer version of QuickOPC, and so on.

Upgrade would certainly be the suggested solution, but you can also try this:

Best regards
The following user(s) said Thank You: andis59

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14 Jan 2022 18:34 #10538 by andis59
I downloaded the newest version of QuickOPC and now it works!

Just have to convince my boss that we must upgrade...

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14 Jan 2022 14:59 #10537 by andis59
I'm using OpcLabs.QuickOpc" version="5.54.1311" and it works perfectly, BUT

Somehow it corrupts the heap memory so that Dapper crashes when a query is returned as a list.
The crash occurs in the ToList() function.
If I remove the initialization of EasyUAClient, then Dapper works (but I need both...)

Has anyone any idea on what the problem is and how to solve it.

private void InitUAClient()
            _easyUAClient = new OpcLabs.EasyOpc.UA.EasyUAClient();
            EasyUAClient.AdaptableParameters.SessionParameters.KeepAliveInterval = 500;
            EasyUAClient.AdaptableParameters.SessionParameters.HoldPeriod = 60 * 1000;
        public static void RegisterManagedResource()
            // Register a license that is we embed as a managed resource in this program.
            // The first two arguments should always be "QuickOPC" and "Multipurpose".
            // The third argument determines the assembly where the license resides.
            // The fourth argument is the namespace-qualified name of the managed resource.
            LicensingManagement.Instance.RegisterManagedResource("QuickOPC", "Multipurpose",

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