this problem is exactly the same as this post http://forums.asp.net/t/1807797.aspx/1?System+Net+Http+is+not+found and this one on StackOverflow
I have all the latest RTM bits, Started a new MVC 4 in .Net 4.5, added the WebAPI nuget package and now my code analysis fails with the same error as reported in the above link.
CA0058 Error Running Code Analysis CA0058 : The referenced assembly 'System.Net.Http, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' could not be found. This assembly is required for analysis and was referenced by: C:ProjectsInHouseTimeRecorderStopGapTimeRecinTimeRec.dll, C:ProjectsInHouseTimeRecorderStopGappackagesMicrosoft.AspNet.WebApi.Core.4.0.20710.0lib
et40System.Web.Http.dll. [Errors and Warnings] - (Global)
From what I can find this seemed to happen with the RC versions because there was a conflict between the .NET 4.5 framework System.Net.Http and the WebApi's version of the System.Net.Http.
The other answers on the StackOverflow response talk about downgrading from .Net 4.5 to 4.0, for obvious reasons, this is not my preferred solution!
See Question&Answers more detail:
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