C:\Program Files (x86)\Reference Assemblies\.NETFramework\v4.5\Facades\System.Threading.Tasks.dll'. Remove one of the duplicate references

Question

Hi when i build my project i get following error

Error 'C:\WS2013\Internet\packages\Microsoft.Bcl.1.1.10\lib\net40\System.Threading.Tasks.dll' and 'C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework.NETFramework\v4.5\Facades\System.Threading.Tasks.dll'. Remove one of the duplicate references. Portal.Web C:\WS2013\Internet\Portal.Web\CSC

i am running vs 2015 on windows 10 machine

If you target .NET 4.5+ remove the BCL package. It's only needed to add async/await support to .NET 4.0 projects — Panagiotis Kanavos

szydzik szydzik · Accepted Answer · 2017-08-24T07:35:35

Unload the project, open the csproj file and remove the references by hand (remove package)

<Reference Include="Microsoft.Threading.Tasks">
  <HintPath>...... Microsoft.Threading.Tasks.dll</HintPath>
</Reference>

@Edit Remove Microsoft.BCL package

C:\Program Files (x86)\Reference Assemblies\.NETFramework\v4.5\Facades\System.Threading.Tasks.dll'. Remove one of the duplicate references

1 Answers