Run a 3.0 project with SDK 3.1.100-rtm-014727, restore failed with error NU1102: Unable to find package Microsoft.AspNetCore.App.Ref with version (= 3.0.1) and package Microsoft.NETCore.App.Host.win-x64 with version (= 3.0.1).

Repro Steps:

1. Only install SDK 3.1.100-rtm-014727
2. Run a 3.0 project

Expected:

Restore and build successfully.

Actual:

Restore failed with error NU1102: error NU1102: Unable to find package Microsoft.AspNetCore.App.Ref with version (= 3.0.1) error NU1102: - Found 12 version(s) in nuget.org [ Nearest version: 3.1.0-preview1.19508.20 ] error NU1102: - Found 0 version(s) in Microsoft Visual Studio Offline Packages error NU1102: Unable to find package Microsoft.NETCore.App.Host.win-x64 with version (= 3.0.1) error NU1102: - Found 10 version(s) in nuget.org [ Nearest version: 3.1.0-preview1.19506.1 ] error NU1102: - Found 0 version(s) in Microsoft Visual Studio Offline Packages

Note:

1. If run a 2.x project, restore and build successfully, run shows as below:

It was not possible to find any compatible framework version
The framework 'Microsoft.NETCore.App', version '2.2.0' was not found.
  - The following frameworks were found:
      3.1.0 at [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
You can resolve the problem by installing the specified framework and/or SDK.
The specified framework can be found at:
  - https://aka.ms/dotnet-core-applaunch?framework=Microsoft.NETCore.App&framework_version=2.2.0&arch=x64&rid=win10-x64

1. If install .net core 3.0 Runtime, it also failed with error NU1102 as above.
2. For VS Master 29517.7(16.5.0 Preview 2.0), install or uninstall .net core 3.0 Runtime, it can restore and build successfully.

Dotnet --info:

.NET Core SDK (reflecting any global.json): Version: 3.1.100 Commit: cd82f021f4

Runtime Environment: OS Name: Windows OS Version: 10.0.17763 OS Platform: Windows RID: win10-x64 Base Path: C:\Program Files\dotnet\sdk\3.1.100\

Host (useful for support): Version: 3.1.0 Commit: 65f04fb6db

.NET Core SDKs installed: 3.1.100 [C:\Program Files\dotnet\sdk]

.NET Core runtimes installed: Microsoft.AspNetCore.App 3.1.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App] Microsoft.NETCore.App 3.1.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App] Microsoft.WindowsDesktop.App 3.1.0 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

To install additional .NET Core runtimes or SDKs: https://aka.ms/dotnet-download

[FilBot3]

What if this is still happening on fresh 3.1.100 installs of dotNet Core SDK?

[FilBot3]

This is my issue.

https://github.com/dotnet/sdk/issues/4156