Nuget.exe Install — Microsoft.CSharp already has a dependency for System.Dynamic.Runtime

The error message already has a dependency defined for usually indicates that the version of NuGet you are using is too old. So you should look at updating it.

This particular error can happen when the NuGet packages being used are using a group dependency with a target framework which the version of NuGet you are using does not know about.

In my case, I get a message when install some Nuget Package:

'PackageA' already has a dependency defined for 'PackageB'

.

And I search PackageB in Nuget Package Manager online, and click install button to install it again,then ran into a problem:

The package requires NuGet client version '2.12' or above, but the current NuGet version is '2.7.40911.287'.

and I do as this solution Nuget version not correct?

after I upgrade the version of Nuget Package Manager, I can install PackageB, and then I can install PackageA.

I had a similar problem using NuGet to load the Google.Apis.Sheets.v4.

Upgrading my VS.NET 2013 from NuGet 2.8.60723.765 to 2.12.0.817 resolved it.

To see your NuGet version number, go to the Package Manager Console prompt (PM>) with Tools / NuGet Package Manager / Package Manager Console. Then, enter "$host" at the PM> prompt.

PM> $hostName             : Package Manager HostVersion          : 2.12.0.817InstanceId       : 38c7734c-3169-4933-b934-23dab18055f2UI               : System.Management.Automation.Internal.Host.InternalHostUserInterfaceCurrentCulture   : en-USCurrentUICulture : en-USPrivateData      : NuGetConsole.Host.PowerShell.Implementation.NuGetPSHost+CommanderIsRunspacePushed : FalseRunspace         : System.Management.Automation.Runspaces.LocalRunspacePM> 

To update NuGet, select Tools / Extensions and Updates... . Then, select "Updates" followed by clicking on the "Update" button of the "NuGet Package Manager".

After the update completes, restart Visual Studio and re-check the NuGet version number.