I added the Json.Net library to Visual Studio 2013 via NuGetpackage and installed it for NetFramework 4.5. I don\'t get an error in Visual Studio when I add
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I had just the same problem in Visual Studio 2015. But Utamaru's solution worked for me.
Make a folder: Assets/Plugins where you put the *.dll file and add it as a reference.
To add a reference you highlight the Analyzers in the Solution Explorer in Visual Studio and under Project > Add Reference you can find your *.dll file located in Assets/Plugin by browsing to it.