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  9. NullReferenceException from EasyOpcUA

NullReferenceException from EasyOpcUA

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08 Apr 2018 12:32 #6212 by support
Replied by support on topic NullReferenceException from EasyOpcUA
Hello,

thanks for reporting this. I have reviewed the related part of code once again, and I think I have found what may be causing it.

A fix for version 2018.1 is now available. It is in build 5.52.147.1 (or later). I have placed it onto our Web; the branded installation is also at its usual place (same as previous build, email me if you are not sure about the link; you can check the build number on the first page of the installation wizard after download).

Note that this particular error is more related to what the server does, how the actual OPC communication looks like and the timing of it; the user code is not that relevant, and it might be impossible for you to reproduce it unless you also have the target server etc. My fix is also "speculative" in this respect.

Best regards

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06 Apr 2018 12:54 #6208 by gkalipershad
NullReferenceException from EasyOpcUA was created by gkalipershad
Hello, I have been working with a customer experiencing an internal error while using EasyOpcUA. Please see the attached screenshot of the full error. The last part of the error states, "Object reference not set to an instance of an object." They are using 5.52.66.2, VS2017, and .NET Framework 4.52.

The issue seemed to be similar to this post: www.opclabs.com/forum/quickopc-ua18/1838-the-opc-ua-subscription-publishing-has-stopped

However, since this customer is on the latest version, it must be something else.

I attempted to obtain the customer's project to try and recreate, then troubleshoot further, but they said they could not provide the entire project, and only included some code. I have included those as well.

Any help would be greatly appreciated.

Thanks.
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