VS2019 Publishing Error : Load an assembly in an incorrect format (Microsoft.CSharp.dll)

Question

I got an error when try to publish a .net library project. Try to troubleshoot it all night but not work. Search in Google and forum but nothing come out. Publish target-runtime is Portable (publish error occur). Change to win-x86 (same error occur).

Environment Info
MS Win 10 x86
MS VSC 2019 v16.11.1
.Net 5.0

Image 1 : Error

Image 2 : Output Log

Diagnostic Log

8/18/2021 3:11:41 PM
System.AggregateException: One or more errors occurred. ---> >Microsoft.WebTools.Shared.Exceptions.WebToolsException: Publish has encountered an error. We were >unable to determine the cause of the error. Check the output log for more details.
--- End of inner exception stack trace ---
---> (Inner Exception #0) Microsoft.WebTools.Shared.Exceptions.WebToolsException: Publish has >encountered an error. We were unable to determine the cause of the error. Check the output log for >more details. <---

Microsoft.WebTools.Shared.Exceptions.WebToolsException: Publish has encountered an error. We were >unable to determine the cause of the error. Check the output log for more details.

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Any idea, help or solution to this problem is really appreaciate and thanks.

Answer 1

Finally, found the answer at GitHub.
https://github.com/dotnet/core/issues/2716

1. Open project Properties.
2. Select Build tab.
3. Go to Output section.
4. Set Generate Serialization Assembly to Auto or Off

Answer 2

Hi,
Put attention to versions of App Functions and version in Visual Studio

Image:
https://imgur.com/a/FAMsmsf