Package 'Microsoft.EntityFrameworkCore.SqlServer' is incompatible with 'all' frameworks in the project
I was using version 1.1. Try to run the below command including the version number:
Visual Studio Code:
'dotnet add package Microsoft.EntityFrameworkCore.SqlServer -v 1.1.1'
Visual Studio:-
'Install-Package Microsoft.EntityFrameworkCore.SqlServer -v 1.1.1'
In order to use version 2.0.0 of EF Core, you need the .NET Core 2.0 SDK and/or Visual Studio 2017 version 15.3.
This Might Be Happening due to generated NuGet Cache While Installing Packages.Go to Tools>Options>NuGet Package Manager>General and "Clear All NuGet Cache".This Worked in my case(VS Community 2019).
Also try to update Source of nuget.org by going to Tools>Options>NuGet Package Manager>Package Source and click Update Source in case of VS 2017.