Error CS8032 An instance of analyzer System.Text.Json.SourceGeneration.JsonSourceGenerator cannot be created

Question

I ran my .Net Framework 4.7.1 project through the .NET Upgrade Assistant to upgrade it to .NET 5 and have been left with the following two errors that are both the same except for the roslyn versioning (3.11 and 4.0).

Error   CS8032  An instance of analyzer System.Text.Json.SourceGeneration.JsonSourceGenerator cannot be created from C:\Users\myAccount\.nuget\packages\system.text.json\6.0.5\analyzers\dotnet\roslyn3.11\cs\System.Text.Json.SourceGeneration.dll : Could not load file or assembly 'Microsoft.CodeAnalysis, Version=3.11.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified..

Error   CS8032  An instance of analyzer System.Text.Json.SourceGeneration.JsonSourceGenerator cannot be created from C:\Users\myAccount\.nuget\packages\system.text.json\6.0.5\analyzers\dotnet\roslyn4.0\cs\System.Text.Json.SourceGeneration.dll : Could not load file or assembly 'Microsoft.CodeAnalysis, Version=3.11.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified..

If I add a nuget package reference to System.Text.Json version 6.0.0, the second error goes away, leaving me with

Error   CS8032  An instance of analyzer System.Text.Json.SourceGeneration.JsonSourceGenerator cannot be created from C:\Users\myAccount\.nuget\packages\system.text.json\6.0.5\analyzers\dotnet\roslyn3.11\cs\System.Text.Json.SourceGeneration.dll : Could not load file or assembly 'Microsoft.CodeAnalysis, Version=3.11.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' or one of its dependencies. The system cannot find the file specified..

I have nuget package references to NHibernate 5.3.12 and Serilog 2.11.0 and no others. I am not sure how to diagnose what could be causing the problem for this project and get it to compile. Any suggestions are appreciated.

Answer 1

So it appears that the addition of the unnecessary System.Text.Json nuget package was a red herring.

It turned out that I was using Visual Studio 2019 (the same IDE we have been using throughout or development of the product pre-upgrade to .NET 5). When I opened the solution in Visual Studio 2022, the underlying errors were actually displayed, easily resolved, and now the solution compiles as expected.