I have a asp.net mvc 5 project in VS2013, after I updated Json.net to the lastest which is 
 <package id="Newtonsoft.Json" version="6.0.1" targetFramework="net451" />
then I run into this error
Error 2 The type 'Newtonsoft.Json.Serialization.CamelCasePropertyNamesContractResolver' exists in both 'c:\Program Files (x86)\Microsoft Visual Studio 12.0\Blend\Newtonsoft.Json.dll' and '{path to my project}\packages\Newtonsoft.Json.6.0.1\lib\net45\Newtonsoft.Json.dll'

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