The type 'System.Data.Services.DataService<T>' exists in both 'c:\Program Files (x86)\Microsoft WCF Data Services\5.0\bin\.NETFramework\Microsoft.Data.Services.dll' and 'c:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.0...

Question

I've installed WCF Data Services 5.0 RTM and added to an existing web project a "WCF Data Service (for OData V3)" item. I've set my DataService type but when I build the project I get these two errors:

• The type 'System.Data.Services.DataService<T>' exists in both 'c:\Program Files (x86)\Microsoft WCF Data Services\5.0\bin\.NETFramework\Microsoft.Data.Services.dll' and 'c:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.0\System.Data.Services.dll'
• The type 'System.Data.Services.DataServiceConfiguration' exists in both 'c:\Program Files (x86)\Microsoft WCF Data Services\5.0\bin\.NETFramework\Microsoft.Data.Services.dll' and 'c:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.0\System.Data.Services.dll'

My .csproj file is below:

<?xml version="1.0" encoding="utf-8"?>
<Project ToolsVersion="4.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <PropertyGroup>
    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
    <ProductVersion>
    </ProductVersion>
    <SchemaVersion>2.0</SchemaVersion>
    <ProjectGuid>{4944278A-7BF9-42EB-BEF3-FECCA51BC755}</ProjectGuid>
    <ProjectTypeGuids>{E53F8FEA-EAE0-44A6-8774-FFD645390401};{349c5851-65df-11da-9384-00065b846f21};{fae04ec0-301f-11d3-bf4b-00c04f79efbc}</ProjectTypeGuids>
    <OutputType>Library</OutputType>
    <AppDesignerFolder>Properties</AppDesignerFolder>
    <RootNamespace>LoggingReportWeb</RootNamespace>
    <AssemblyName>LoggingReportWeb</AssemblyName>
    <TargetFrameworkVersion>v4.0</TargetFrameworkVersion>
    <MvcBuildViews>false</MvcBuildViews>
    <UseIISExpress>false</UseIISExpress>
  </PropertyGroup>
  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
    <DebugSymbols>true</DebugSymbols>
    <DebugType>full</DebugType>
    <Optimize>false</Optimize>
    <OutputPath>..\..\build\LoggingReportWeb\bin\</OutputPath>
    <DefineConstants>DEBUG;TRACE</DefineConstants>
    <ErrorReport>prompt</ErrorReport>
    <WarningLevel>4</WarningLevel>
  </PropertyGroup>
  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">
    <DebugType>pdbonly</DebugType>
    <Optimize>true</Optimize>
    <OutputPath>bin\</OutputPath>
    <DefineConstants>TRACE</DefineConstants>
    <ErrorReport>prompt</ErrorReport>
    <WarningLevel>4</WarningLevel>
  </PropertyGroup>
  <ItemGroup>
    <Reference Include="Microsoft.Data.Edm, Version=5.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL" />
    <Reference Include="Microsoft.Data.OData, Version=5.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL" />
    <Reference Include="Microsoft.Data.Services, Version=5.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL" />
    <Reference Include="Microsoft.Data.Services.Client, Version=5.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL" />
    <Reference Include="Microsoft.ReportViewer.Common, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
      <HintPath>..\..\_Resources\ReportViewer\Microsoft.ReportViewer.Common.dll</HintPath>
      <Private>True</Private>
    </Reference>
    <Reference Include="Microsoft.ReportViewer.WebForms, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL">
      <SpecificVersion>False</SpecificVersion>
      <HintPath>..\..\_Resources\ReportViewer\Microsoft.ReportViewer.WebForms.dll</HintPath>
      <Private>True</Private>
    </Reference>
    <Reference Include="System.Data.Entity" />
    <Reference Include="System.Data.Services" />
    <Reference Include="System.Data.Services.Client" />
    <Reference Include="System.Runtime.Serialization" />
    <Reference Include="System.Security" />
    <Reference Include="System.ServiceModel" />
    <Reference Include="System.ServiceModel.Web" />
    <Reference Include="System.Spatial, Version=5.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL" />
    <Reference Include="System.Web.Mvc, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL" />
    <Reference Include="System.Web.WebPages, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL" />
    <Reference Include="System.Web.Helpers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL" />
    <Reference Include="Microsoft.CSharp" />
    <Reference Include="System" />
    <Reference Include="System.Data" />
    <Reference Include="System.Drawing" />
    <Reference Include="System.Web.ApplicationServices" />
    <Reference Include="System.ComponentModel.DataAnnotations" />
    <Reference Include="System.Core" />
    <Reference Include="System.Data.DataSetExtensions" />
    <Reference Include="System.Web" />
    <Reference Include="System.Web.Extensions" />
    <Reference Include="System.Web.Abstractions" />
    <Reference Include="System.Web.Routing" />
    <Reference Include="System.Configuration" />
    <Reference Include="System.Web.Services" />
    <Reference Include="System.EnterpriseServices" />
    <Reference Include="System.Xml" />
  </ItemGroup>
  <ItemGroup>
    <Compile Include="Controllers\ReportController.cs" />
    <Compile Include="DataWarehouse.Designer.cs">
      <DependentUpon>DataWarehouse.edmx</DependentUpon>
      <AutoGen>True</AutoGen>
      <DesignTime>True</DesignTime>
    </Compile>
    <Compile Include="DataWarehouse.svc.cs">
      <DependentUpon>DataWarehouse.svc</DependentUpon>
    </Compile>
    <Compile Include="Global.asax.cs">
      <DependentUpon>Global.asax</DependentUpon>
    </Compile>
    <Compile Include="Models\Report\ReportSetting.cs" />
    <Compile Include="Properties\AssemblyInfo.cs" />
    <Compile Include="ReportRouteHandler.cs" />
    <Compile Include="Reports\ReportWebForm.aspx.cs">
      <DependentUpon>ReportWebForm.aspx</DependentUpon>
      <SubType>ASPXCodeBehind</SubType>
    </Compile>
    <Compile Include="Reports\ReportWebForm.aspx.designer.cs">
      <DependentUpon>ReportWebForm.aspx</DependentUpon>
    </Compile>
  </ItemGroup>
  <ItemGroup>
    <Content Include="DataWarehouse.svc" />
    <Content Include="Global.asax" />
    <Content Include="Reports\ReportWebForm.aspx" />
    <Content Include="Web.config" />
    <Content Include="Views\Web.config" />
    <Content Include="Views\_ViewStart.cshtml" />
    <Content Include="Views\Shared\Error.cshtml" />
    <Content Include="Views\Shared\_Layout.cshtml" />
    <None Include="_bin_deployableAssemblies\Microsoft.Web.Infrastructure.dll" />
    <None Include="_bin_deployableAssemblies\System.Web.WebPages.Razor.dll" />
    <None Include="_bin_deployableAssemblies\System.Web.WebPages.dll" />
    <None Include="_bin_deployableAssemblies\System.Web.WebPages.Deployment.dll" />
    <None Include="_bin_deployableAssemblies\System.Web.Razor.dll" />
    <None Include="_bin_deployableAssemblies\System.Web.Helpers.dll" />
    <None Include="_bin_deployableAssemblies\System.Web.Mvc.dll" />
  </ItemGroup>
  <ItemGroup>
    <Folder Include="Content\" />
    <Folder Include="Scripts\" />
  </ItemGroup>
  <ItemGroup>
    <Content Include="Views\Report\Index.cshtml" />
  </ItemGroup>
  <ItemGroup>
    <EntityDeploy Include="DataWarehouse.edmx">
      <Generator>EntityModelCodeGenerator</Generator>
      <LastGenOutput>DataWarehouse.Designer.cs</LastGenOutput>
    </EntityDeploy>
  </ItemGroup>
  <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
  <Import Project="$(MSBuildExtensionsPath32)\Microsoft\VisualStudio\v10.0\WebApplications\Microsoft.WebApplication.targets" />
  <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
       Other similar extension points exist, see Microsoft.Common.targets.
  <Target Name="BeforeBuild">
  </Target>
  <Target Name="AfterBuild">
  </Target> -->
  <Target Name="MvcBuildViews" AfterTargets="AfterBuild" Condition="'$(MvcBuildViews)'=='true'">
    <AspNetCompiler VirtualPath="temp" PhysicalPath="$(WebProjectOutputDir)" />
  </Target>
  <ProjectExtensions>
    <VisualStudio>
      <FlavorProperties GUID="{349c5851-65df-11da-9384-00065b846f21}">
        <WebProjectProperties>
          <UseIIS>False</UseIIS>
          <AutoAssignPort>True</AutoAssignPort>
          <DevelopmentServerPort>50597</DevelopmentServerPort>
          <DevelopmentServerVPath>/</DevelopmentServerVPath>
          <IISUrl>
          </IISUrl>
          <NTLMAuthentication>False</NTLMAuthentication>
          <UseCustomServer>False</UseCustomServer>
          <CustomServerUrl>
          </CustomServerUrl>
          <SaveServerSettingsInUserFile>False</SaveServerSettingsInUserFile>
        </WebProjectProperties>
      </FlavorProperties>
    </VisualStudio>
  </ProjectExtensions>
  <PropertyGroup>
    <PostBuildEvent>xcopy /Y/D/S/I "$(ProjectDir)*.svc" "$(TargetDir)..\"
xcopy /Y/D/S/I "$(ProjectDir)*.config" "$(TargetDir)..\"
xcopy /Y/D/S/I "$(ProjectDir)*.edmx" "$(TargetDir)..\"
xcopy /Y/D/S/I "$(ProjectDir)*.cshtml" "$(TargetDir)..\"
xcopy /Y/D/S/I "$(ProjectDir)*.aspx" "$(TargetDir)..\"
xcopy /Y/D/S/I "$(ProjectDir)*.asax" "$(TargetDir)..\"</PostBuildEvent>
  </PropertyGroup>
</Project>

Answer 1

I removed and re-added a bunch of references (anything containing the words Data, Entity, Services etc) and that seems to have fixed it. I think the simple version of the fix is to remove the reference to System.Data.Services as it's no longer needed and is replaced by Microsoft.Data.Services.

Answer 2

Hi tjrobinson,

Thanks for sharing your experience here.

Have a nice day.

---

Alan Chen[MSFT]
MSDN Community Support | Feedback to us
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