How to bypass Microsoft.Bcl.Build warning

Question

I have a solution with multiple projects, one of them has this build warning that shows

All projects referencing Project.csproj must install nuget

Answer 1

How can I Remove/Suppress/Bypass this particular warning?

You can add a parameter named Properties with value SkipValidatePackageReferences=true to to disable for projectreferences from projects that don't yet support Nuget, which is safe. Like this:

<ItemGroup>
    <ProjectReference Include="..\MyProject\Project.csproj">
      <Name> Project</Name>
      <Project>{77ACF4A4-5F19-40E9-991D-BDB09B175366}</Project>
      <Private>True</Private>
      <RoleType>Web</RoleType>
      <RoleName>MyProject</RoleName>
      <UpdateDiagnosticsConnectionStringOnPublish>True</UpdateDiagnosticsConnectionStringOnPublish>
      <Properties>SkipValidatePackageReferences=true</Properties>
    </ProjectReference>
  </ItemGroup>

Answer 2

I have resolved the issue by completely removing all Microsoft.Bcl and Microsoft.Bcl.Build references as @nozzleman suggested in comments.

Although no dll references were present in the References list in solution explorer, there were entries in package.config for those 2 packages as below:

<package id="Microsoft.Bcl" version="1.1.10" targetFramework="net461" />
<package id="Microsoft.Bcl.Build" version="1.0.14" targetFramework="net461" />

I did a search (Ctrl + F) in full solution for the terms Microsoft.Bcl and Microsoft.Bcl.Build and removed all those entries from packages.config and also from .csproj files which had entries like below:

<Import Project="..\packages\Microsoft.Bcl.Build.1.0.14\tools\Microsoft.Bcl.Build.targets" Condition="Exists('..\packages\Microsoft.Bcl.Build.1.0.14\tools\Microsoft.Bcl.Build.targets')" />
  <Target Name="EnsureBclBuildImported" BeforeTargets="BeforeBuild" Condition="'$(BclBuildImported)' == ''">
    <Error Condition="!Exists('..\packages\Microsoft.Bcl.Build.1.0.14\tools\Microsoft.Bcl.Build.targets')" Text="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=317567." HelpKeyword="BCLBUILD2001" />
    <Error Condition="Exists('..\packages\Microsoft.Bcl.Build.1.0.14\tools\Microsoft.Bcl.Build.targets')" Text="The build restored NuGet packages. Build the project again to include these packages in the build. For more information, see http://go.microsoft.com/fwlink/?LinkID=317568." HelpKeyword="BCLBUILD2002" />
  </Target>

Those lines were appended when it was installed before and as someone manually removed references by pressing Delete key, they were not removed.

After cleaning those 2 items from everywhere the warning is gone from build.