title: Compiler Error Message: CS0433: The type 'System.Web.Helpers.Json' exists in both
body: <p>I just checked out a .NET project to work on. However, when I run it, it gives me this compile error:</p>
  
  <blockquote>
    <p>Compiler Error Message: CS0433: The type 'System.Web.Helpers.Json' exists in both 'c:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files\root\2c3c3525\f643d2c6\assembly\dl3\a363418d\c830c6f0_9d86d001\System.Web.Helpers.DLL' and 'c:\Windows\Microsoft.NET\assembly\GAC_MSIL\System.Web.Helpers\v4.0_2.0.0.0__31bf3856ad364e35\System.Web.Helpers.dll'</p>
    
    <p>Line 57:             db.SubmitChanges();
    Line 58: 
    Line 59:             Context.Response.Write(Json.Encode(new { success = true }));
    Line 60: 
    Line 61:         }</p>
  </blockquote>
  
  <p>I tried to look for solution online but it didn't help. The steps I followed:</p>
  
  <p>Manually deleting everything all the content inside the TEMP file
  adding batch="false" in compilation tag in the webconfig file</p>
  
  <p>None of them helped... Anyone has any idea?</p>