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Error DNN upgrade to 9.13.5 System.Runtime.CompilerServices.Unsafe

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Daniel Valadas

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1/29/2025 1:43 PM

So this boils down to a mismatch between the dll in the bin folder, the web(dot)config redirects and what some other dll needs to work.
The normal way is that all extensions declare the version they need in their manifest and DNN we automatically create a binding redirect in the web(dot)config so that all extensions are fed the highest version. This is not perfect but in your current situation either the dll is of the wrong version (right click on it and look at the details) or the web(dot)config has a binding redirect to a version that is not present in the web(dot)config folder, or some extension did not declare its dependency on it in their web(dot)config. Let's start from knowing the versions of the DLL and if you find it in the web(dot)config. Then you can check if you see it listed in the database table "Assemblies" which should tell which module depends on it and which version (throught the PackageID reference to the Packages table).

Daniel Valadas

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1/29/2025 1:47 PM

If I remember correctly it polyfills many modern .Net APIs so they can work on .NetStandard

willem

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1/30/2025 10:45 AM

We only use DNNSharp Action Form in this DNN instance not 2SXC

So dll version in bin, in web . config reference and record in assemblies table should be the same?

Dll details is file version 4.700.20.12001 so I put 4.7.2.1 in the web . config reference?

3ART Technologies Company

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1/30/2025 2:57 PM

This error occurs when DNN 9.13.5 is trying to use a version of System.Runtime.CompilerServices.Unsafe that does not match the expected version (4.0.6.0). This is usually due to an outdated or incorrect assembly reference.

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