C # install-package: "XX" already has a dependency defined for "XXX"

Maybe the version of NuGet itself is behind the version of the adaptation package

Visual Studio 2013 Update NuGet Package Manager

• Ø Preface

When you use the NuGet Package Manager in Visual Studio to download a program, you may sometimes get a similar error:"Newtonsoft.json" already has a dependency defined for "Netstandard.library".

The effective way to resolve this error is to update the NuGet Package Manager, as shown in Visual Studio Ultimate 2013 below, for specific steps to update the NuGet Package Manager.

1. 1. Open Visual Studio 2013.
2. 2. Select extensions and Updates, tools, menu bar.
3. 3. in the "Installed" option, locate the NuGet Package Manager and uninstall it.

1. 4. After uninstalling the NuGet Package Manager, restart Visual Studio and repeat step 2.
2. 5. Search for "NuGet" in the "online" option, select NuGet package Manager to download and install automatically when the download is complete.

1. 6. After the installation is complete, restart Visual studio,ok.

• Ø Summary

In fact, updating the NuGet Package Manager is a process of uninstalling and installing.

C # install-package: "XX" already has a dependency defined for "XXX"