Visual studio 2019 v16.6 can't build .net5 console application and raise errors: .NETFramework,Version=v5.0 were not found

Question

Development Environment:

• Visual studio 2019 v16.6.2 is installed
• .Net5 preview 5 is installed

Microsoft.NETCore.App 5.0.0-preview.5.20278.1 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]

• Enable the designer in Visual Studio

Tools > Options > Environment > Preview Features and select the Use the preview Windows Forms designer for .NET Core apps option. > re-start vs

I followed the instructions in this answer

I created a demo console project in .net5

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net5.0</TargetFramework>
  </PropertyGroup>  
</Project>

Then build and run using dotnet cli is ok

dotnet build  #ok
dotnet run # ok

Trying to build the project in visual studio fail with errors

Error MSB3644 The reference assemblies for .NETFramework,Version=v5.0 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

Error NETSDK1005 Assets file 'F:\projects\Net5Demo\obj\project.assets.json' doesn't have a target for '.NETFramework,Version=v5.0'. Ensure that restore has run and that you have included 'net50' in the TargetFrameworks for your project.

What I missed to build and run the project using vs 2019 v16.6.2 ?

Answer 1

As per https://dotnet.microsoft.com/download/dotnet/5.0 it looks like you also need VS 2019 16.8 preview 3 for it to recognize it.

Edit: I was having the same issue and after I installed VS 2019 16.8 preview 3 it started showing the option to use .NET 5.0.

Answer 2

• Update Visual Studio to Visual Studio 2019 version 16.7 (released on Aug 5,2020 with support c# 9)

 help -> check for updates -> visual studio installer is displayed -> click update

• Enable the designer in Visual Studio 2019 (as in OP).
• Update to SDK 5.0.100-preview.7.

Just to check c# 9 availability, in the developer Command Prompt, type the command:

csc -langversion:?

You get:

Supported language versions:
default
1
2
3
4
5
6
7.0
7.1
7.2
7.3
8.0 (default)
9.0
latestmajor
preview
latest

The list above include 9.0 and you LangVersion can be defined as 9.0: The Console project with c# 9 support, can be:

<PropertyGroup>
  <OutputType>Exe</OutputType>
  <TargetFramework>net5.0</TargetFramework>
  <LangVersion>9.0</LangVersion> 
</PropertyGroup>

Now VS 2019 v16.7 can compile c# 9 in NET 5 successfully and IDE support C# 9.

Update: Sep15,2020

Vs 2019 16.7.3 is supporting only Preview7.

Full version
    5.0.100-preview.7.20366.6
Visual Studio support
    Visual Studio 2019 (v16.7, latest preview)
    Visual Studio 2019 for Mac (v8.7 preview)

In Download .Net 5 page, you can find the official VS2019 support. It seems that 16.7.3 is supporting only preview7.

Answer 3

Have you downloaded the x64 or the x86 version of the SDK?

You may try to download the preview 6.

Answer 4

Maybe you need to enable previews in Visual Studio:

Go to Tools > Options and enter Preview Features in the left panel.

Then in the right panel enable Use previews of the .NET Core SDK (requires restart)

Answer 5

My VS is 16.7.3 (the latest). But, when I install, SDK 5.0.100-preview.8, I don't see .Net 5.0 on my Target framework. But, after uninstalling it and reinstalling SDK 5.0.100-preview.7, I could see it.