The current .NET SDK does not support targeting .NET Core 2.1. Either target .NET Core 2.0 or lower, or use a .NET SDK that supports .NET Core 2.1

Question

have tried upgrading to the professional version of visual studio 2017 v 15.6.0 (Preview 7.0)

and installed aspnetcore-runtime-2.1.0-preview1-final-win-x64 and .net

Answer 1

I had this problem and I did a fresh install of VS2017. That fixed it!