The reference assemblies for framework .NETCore, Version=v5.0 were not found

Question

I have a UWP project that was created using Visual Studio 2017. It builds fine on this machine (machine 1).

However, when I copy the project over to a machine (machine 2) where I only have the Visual Studio 2017 Build Tools installed, and attempt to build it using MSBuild, I get the following error:

C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\MSBuild\15.0\Bin\Microsoft.Common.CurrentVersion.targets
(1126,5): error MSB3644: The reference assemblies for framework ".NETCore,Version=v5.0" were not found. To resolve this
, install the SDK or Targeting Pack for this framework version or retarget your application to a version of the framewo
rk for which you have the SDK or Targeting Pack installed. Note that assemblies will be resolved from the Global Assemb
ly Cache (GAC) and will be used in place of reference assemblies. Therefore your assembly may not be correctly targeted
 for the framework you intend. [<path_to_my_UWP_project>\UWP.csproj]

I suspect the need for .NetCore v5.0 arises from this line in my UWP.csproj file:

< PackageReference Include="Microsoft.NETCore.UniversalWindowsPlatform" Version="6.0.1" />

I do a nuget restore before I build on machine 2, and I can see that microsoft.netcore.universalwindowsplatform successfully gets restored under < C_Users_me >/.nuget/packages, and so does microsoft.netcore.

On machine 1 however, only microsoft.netcore.universalwindowsplatform gets restored but it still builds fine via Visual Studio.

Question: Why am I getting this error and how do I fix the problem?

Answer 1

I was getting the same error message. The resolution was to install the latest version of Visual Studio 2019. I had version 16.6 installed on my computer. I needed version 16.8 installed. Once I did the install, the error message went away.

Initial reason for this issue: I had received a VS C# solution from another individual. Apparently there was something in the solution that stated it required some library (.NETFramework v=5.0) which was not in 16.4 but was in 16.8.

The help instructions on the VS error message did not help; there is currently no .NETFramework, version=v5.0. There is only a .NET Core Version=5.0 or a .NetFramework Version=v4.8

This gitHub post lead me to the correct soltuion.