VSTS Continuous Integration: NuGet package are missing on this computer - msbuild

Question

I am using Visual Studio 2015, i have a solution with 2 different web applications. There exists One Solution and two projects under it. The files related to nuget are distributed as:
Packages Folder is in the Solution Directory
Package.config in each project directory
There is no nuget folder: nuget.config and nuget.exe in my solution.
My Project build and run fine in Visual Studio, but I am facing a problem when using VSTS Continuous Integration with Build Solution Step (which use a build definition that maps to one project) it gives:
This project references NuGet package(s) that are missing on this computer. Use
NuGet Package Restore to download them. For more information, see The missing file is
..\packages\Microsoft.Net.Compilers.1.0.0\build\Microsoft.Net.Compilers.props.
This is MyProject.csproj file:
<?xml version="1.0" encoding="utf-8"?>
<Project ToolsVersion="14.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
<Import Project="..\packages\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.1.0.0\build\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.props" Condition="Exists('..\packages\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.1.0.0\build\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.props')" />
<Import Project="..\packages\Microsoft.Net.Compilers.1.0.0\build\Microsoft.Net.Compilers.props" Condition="Exists('..\packages\Microsoft.Net.Compilers.1.0.0\build\Microsoft.Net.Compilers.props')" />
<Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" />
<PropertyGroup>
<Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
<Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
<ProductVersion>
</ProductVersion>
<SchemaVersion>2.0</SchemaVersion>
<ProjectGuid>{BBD26A49-D1F4-4391-9D60-2469433DEE0D}</ProjectGuid>
<ProjectTypeGuids>{349c5851-65df-11da-9384-00065b846f21};{fae04ec0-301f-11d3-bf4b-00c04f79efbc}</ProjectTypeGuids>
<OutputType>Library</OutputType>
<AppDesignerFolder>Properties</AppDesignerFolder>
<RootNamespace>AdminUI</RootNamespace>
<AssemblyName>AdminUI</AssemblyName>
<TargetFrameworkVersion>v4.5.2</TargetFrameworkVersion>
<MvcBuildViews>false</MvcBuildViews>
<UseIISExpress>true</UseIISExpress>
<IISExpressSSLPort />
<IISExpressAnonymousAuthentication />
<IISExpressWindowsAuthentication />
<IISExpressUseClassicPipelineMode />
<UseGlobalApplicationHostFile />
<SccProjectName>SAK</SccProjectName>
<SccLocalPath>SAK</SccLocalPath>
<SccAuxPath>SAK</SccAuxPath>
<SccProvider>SAK</SccProvider>
<NuGetPackageImportStamp>
</NuGetPackageImportStamp>
</PropertyGroup>
<PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
I noticed that it only tries to import the package that generated the error, but it doesn't explicitly import other packages, but it include them as references:
<Reference Include="WebGrease">
<Private>True</Private>
<HintPath>..\packages\WebGrease.1.5.2\lib\WebGrease.dll</HintPath>
</Reference>
<Reference Include="Antlr3.Runtime">
<Private>True</Private>
<HintPath>..\packages\Antlr.3.4.1.9004\lib\Antlr3.Runtime.dll</HintPath>
</Reference>
This also the end of the myProject.csproj file:
<Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
<PropertyGroup>
<ErrorText>This project references NuGet package(s) that are missing on this computer. Use 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('..\packages\Microsoft.Net.Compilers.1.0.0\build\Microsoft.Net.Compilers.props')" Text="$([System.String]::Format('$(ErrorText)', '..\packages\Microsoft.Net.Compilers.1.0.0\build\Microsoft.Net.Compilers.props'))" />
<Error Condition="!Exists('..\packages\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.1.0.0\build\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.props')" Text="$([System.String]::Format('$(ErrorText)', '..\packages\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.1.0.0\build\Microsoft.CodeDom.Providers.DotNetCompilerPlatform.props'))" />
</Target>
I am wondering why it gives this error, taking into consideration that this package is already installed in the previous step "Nugget Install". Why it can't find it? i have spent a lot of time on this issue!

Answer 1

Before you add the build task, you can add nuget install or restore task. This will restore/install the nuget packages on the build agent.

Answer 2

Actually, this worked for me:
Adding the mapping (repository configuration) to the packages folder in the solution
Repository Configuration
Nuget Install Config
Then, it worked like a charm.

Answer 3

Ensure the Package.config file you've mentioned exists in source control.
It may be that everything builds successfully on your machine because Package.config exists there but not in source control for when the continuous integration agent tries to download and build the project.