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 core SDK 2.1.4.

When I created a new web application I get an error saying

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

When I try to build an existing project I get an error

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

I don't see ".net core 2.1" in my target framework

I don't have global.json file in my computer

When I try dotnet --info, I get this

c:\source\dnacloud\testapp>dotnet --info .NET Command Line Tools (2.1.100)

Product Information:
Version: 2.1.100
Commit SHA-1 hash: b9e74c6

Runtime Environment:
OS Name: Windows
OS Version: 10.0.16299
OS Platform: Windows
RID: win10-x64
Base Path: C:\Program Files\dotnet\sdk\2.1.100\

Microsoft .NET Core Shared Framework Host

Version : 2.0.5
Build : 17373eb129b3b05aa18ece963f8795d65ef8ea54

Answer 1

The problem here is that Microsoft confused a whole lot of people with how they numbered their .NET Core SDKs.

In the original poster's message the path C:\Program Files\dotnet\sdk\2.1.100\ DOES NOT appear to represent the .NET Core 2.1 runtime (but you'd think it does).

I came across this post The current .NET SDK does not support targeting .NET Core 2.1 on developercommunity.visualstudio.com where a Microsoft support person explains the confusion:

"Thank you for your feedback! We have determined that this issue is not a bug. The first SDK with .NET Core 2.1 support is 2.1.300-preview1. We know the versioning is confusing which is why starting in 2.1.300, the major.minor versions of the SDK will now be aligned with the major.minor versions of the runtime as well."

So ... in order to get .NET Core 2.1 support for building via the SDK you need to install the SDK with version 2.1.300 at least (since 2.1.2 is NOT .NET Core 2.1) ... yeah, confusing. Thank you Microsoft for some lost time on this.