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Could not load file or assembly...

29 Mar 2021 12:45 #9579 by support

First, please check that the assembly specified in the exception message is actually present on the disk, together with the other assemblies of your application. I understand that you *are* referencing it; but there are sometimes issues with Visual Studio not copying the assembly to the output folder, or similar problems.

If the assembly file is present where it should be: The next thing to consider is the reason mentioned in the exception message, i.e. missing C++ redistributable libraries. Normally QuickOPC uses a special technique so that no such prerequisite needs to be installed, but it may fail under special circumstances. ( )

The link to the proper version of the C++ redistributables (warning - there are many version of them!) is installed with the product, specific to the version you are using (question: which version are you using?). For the current version (2021.1) and some versions below, the link is .

Best regards
The following user(s) said Thank You: Ai2Infinity

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29 Mar 2021 10:20 #9578 by Ai2Infinity
Good morning,

I have an issue with when writing to tags from an web page after deployment. It runs fine on my local machine in source code. For context, I have a .net application running on the deployed machine and it runs fine. It is just the ASP.Net Web Page that is the issue. I have installed the OPCLabs redistributable package on the remote machine.

I have attached screen shot of error and current reference list in ASP.Net project.

Thank you for your help.


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