GlobalConfiguration.Configure() not present after Web API 2 and .NET 4.5.1 migration

I recently started following this guide to migrate my project to .NET 4.5.1 and Web Api 2.

The very first thing MS developer Rick Anderson asks you to do is change:

WebApiConfig.Register(GlobalConfiguration.Configuration);

to

GlobalConfiguration.Configure(WebApiConfig.Register);

in the global.asax file. Yet this is giving me an error when I try to build:

Error 1 'System.Web.Http.GlobalConfiguration' does not contain a definition for 'Configure'

My project is currently on MVC 5 and Web Api 2 and .NET 4.5.1, yet I think System.Web.Http still thinks it's the .NEt 4.0 version.

How can I go about fixing this?

Thank you.

Edit:

Here are my assembly bindings:

<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
  <dependentAssembly>
    <assemblyIdentity name="System.Net.Http.Formatting" publicKeyToken="31BF3856AD364E35" culture="neutral"/>
    <bindingRedirect oldVersion="0.0.0.0-5.0.0.0" newVersion="5.0.0.0"/>
  </dependentAssembly>
  <!--
  <dependentAssembly>
    <assemblyIdentity name="System.Web.Helpers" publicKeyToken="31bf3856ad364e35"/>
    <bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0"/>
  </dependentAssembly>
  <dependentAssembly>
    <assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35"/>
    <bindingRedirect oldVersion="1.0.0.0-5.0.0.0" newVersion="5.0.0.0"/>
  </dependentAssembly>
  <dependentAssembly>
    <assemblyIdentity name="System.Web.WebPages" publicKeyToken="31bf3856ad364e35"/>
    <bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0"/>
  </dependentAssembly>
  <dependentAssembly>
    <assemblyIdentity name="System.Web.Http" publicKeyToken="31bf3856ad364e35"/>
    <bindingRedirect oldVersion="1.0.0.0-5.0.0.0" newVersion="5.0.0.0"/>
  </dependentAssembly>
  <dependentAssembly>
    <assemblyIdentity name="System.Web.WebPages.Razor" publicKeyToken="31bf3856ad364e35"/>
    <bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0"/>
  </dependentAssembly> -->
</assemblyBinding>

Everything commented out after the top was commented because I was getting the error:

Warning 2 Found conflicts between different versions of the same dependent assembly that could not be resolved. These reference conflicts are listed in the build log when log verbosity is set to detailed.

and getting rid of the hard bindings was fixing that.

It needs the system.web.http.webhost which is part of this package. I fixed this by installing the following package:

PM> Install-Package Microsoft.AspNet.WebApi.WebHost 

or search for it in nuget https://www.nuget.org/packages/Microsoft.AspNet.WebApi.WebHost/5.1.0

None of these ideas helped my project using MVC 5.2.2.

• System.web.Http 5.2.2 was already installed
• Deleting the Packages folder and completely re-downloading all NuGet libraries did nothing
• Web.config already had a dependentAssembly entry for System.Web.Http

Forcing a reinstall corrected the problem. From the NuGet package manager console:

update-Package -reinstall Microsoft.AspNet.WebApi.WebHost

GlobalConfiguration class is part of Microsoft.AspNet.WebApi.WebHost nuget package...Have you upgraded this package to Web API 2?

As well as using Package manager console to get nuget to update the project with Install-Package Microsoft.AspNet.WebApi.WebHost for missing GlobalConfiguration,

I needed Install-Package Microsoft.AspNet.WebApi.SelfHost for missing using System.Web.Http;