Detected package downgrade: Microsoft.NETCore.App from 2.1.3 to 2.1.0

Question

I try to update my .net solution from .NET Core 1.1 to .NET Core 2.1. I have several .NET Core and .NET standard projects inside, which reference each other and another NuGe

Answer 1

I had a missing version in the csproj file.

Adding the version fixed the issue.

Answer 2

I also had this problem after installing a new version of .Net Core (2.0 to 2.1). The below link gave me a hint of what caused the problem.

https://github.com/dotnet/cli/issues/9433

The solution for me was to change the project's Target Framework to the latest installed .Net Core version.

Project Properties > Application > Target Framework