When I installed Visual Studio 2019 and MG 3.8, I also followed the Getting Started documentation. From what I remember, I didn’t get any errors, so I’m not sure what went wrong for you there.
My issues with this error in 3.8 seem to be isolated to individual projects, so creating a new project, or uninstalling/reinstalling nuget packages does the trick.
If you are having issues from the get go with all MG 3.8 projects…
- Make sure you are using VS 2019.
- Make sure you’ve installed the Monogame extension, mgcb editor etc.
There’s not need to install XNA seperately, so that may be causing the issue.
Other than uninstall/reinstall, there isn’t much I can suggest.