Build error, This project references NuGet

Quick solution that worked like a charm for me and others:

If you are using VS 2015+, just remove the following lines from the .csproj file of your project:

  <Import Project="$(SolutionDir)\.nuget\NuGet.targets" Condition="Exists('$(SolutionDir)\.nuget\NuGet.targets')" />
  <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
    <PropertyGroup>
      <ErrorText>This project references NuGet package(s) that are missing on this computer. Enable NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
    </PropertyGroup>
    <Error Condition="!Exists('$(SolutionDir)\.nuget\NuGet.targets')" Text="$([System.String]::Format('$(ErrorText)', '$(SolutionDir)\.nuget\NuGet.targets'))" />
  </Target>

In VS 2015+ Solution Explorer:

1. Right-click project name -> Unload Project
2. Right-click project name -> Edit .csproj
3. Remove the lines specified above from the file and save
4. Right-click project name -> Reload Project

First I would check if your MusicKarma project has Microsoft.Net.Compilers in its packages.config file. If not then you could remove everything to do with that NuGet package from your MusicKarma.csproj.

If you are using the Microsoft.Net.Compilers NuGet package then my guess is that the path is incorrect. Looking at the directory name in the error message I would guess that the MusicKarma solution file (.sln) is in the same directory as the MusicKarma.csproj. If so then the packages directory is probably wrong since by default the packages directory would be inside the solution directory. So I am assuming that your packages directory is:

C:\Users\Bryan\Documents\Visual Studio 2015\Projects\MusicKarma\packages

Whilst your MusicKarma.csproj file is looking for the props file in:

C:\Users\Bryan\Documents\Visual Studio 2015\Projects\packages\Microsoft.Net.Compilers.1.1.1\build

So if that is the case then you can fix the problem by editing the path in your MusicKarma.csproj file or by reinstalling the NuGet package.

This problem appeared for me when I was creating folders in the filesystem (not in my solution) and moved some projects around.

Turns out that the package paths are relative from the csproj files. So I had to change the "HintPath" of my references:

<Reference Include="EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089, processorArchitecture=MSIL">
    <HintPath>..\packages\EntityFramework.6.1.3\lib\net45\EntityFramework.dll</HintPath>
    <Private>True</Private>
</Reference>

To:

<Reference Include="EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089, processorArchitecture=MSIL">
    <HintPath>..\..\packages\EntityFramework.6.1.3\lib\net45\EntityFramework.dll</HintPath>
    <Private>True</Private>
</Reference>

Notice the double "..\" in 'HintPath'.

I also had to change my error conditions, for example I had to change:

<Error Condition="!Exists('..\packages\Microsoft.Net.Compilers.1.1.1\build\Microsoft.Net.Compilers.props')" Text="$([System.String]::Format('$(ErrorText)', '..\packages\Microsoft.Net.Compilers.1.1.1\build\Microsoft.Net.Compilers.props'))" />

To:

<Error Condition="!Exists('..\..\packages\Microsoft.Net.Compilers.1.1.1\build\Microsoft.Net.Compilers.props')" Text="$([System.String]::Format('$(ErrorText)', '..\..\packages\Microsoft.Net.Compilers.1.1.1\build\Microsoft.Net.Compilers.props'))" />

Again, notice the double "..\".

I also had this error I took this part of code from .csproj file:

 <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
      <PropertyGroup>
        <ErrorText>This project references NuGet package(s) that are missing on this computer. Enable NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
      </PropertyGroup>
      <Error Condition="!Exists('$(SolutionDir)\.nuget\NuGet.targets')" Text="$([System.String]::Format('$(ErrorText)', '$(SolutionDir)\.nuget\NuGet.targets'))" />
    </Target>

delete that part of code. if you open the file .csproj with notepad, delete the Targuet code, save, and open normaly