Currently I have Entity Framework 5.0 installed in Visual Studio 2012. For some reason the project only is supported by EF 188.8.131.52.
So I installed EF 184.108.40.206 but I have the error in the Nuget command line:
PM> Install-Package EntityFramework -Version 220.127.116.11 Install-Package : Unable to find version '18.104.22.168' of package 'EntityFramework'. At line:1 char:1 + Install-Package EntityFramework -Version 22.214.171.124 + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + CategoryInfo : NotSpecified: (:) [Install-Package], InvalidOperationException + FullyQualifiedErrorId : NuGetCmdletUnhandledException,NuGet.PowerShell.Commands.InstallPackageCommand
The versioning headache you are seeing is due to differences in what EF can support depending on what version of the .NET run time your app is targeting.
If you are targeting .NET 4 and install EF 5, the assembly version will be 4.4
If you are targeting .NET 4.5 and install EF 5, the assembly version will be 5.0
This is because things such as DBGeography only can work if .NET 4.5 is present.
Just install EF 5 proper and the NuGet package will figure this out and give you the proper version.
tl;tr When you need assembly version 126.96.36.199 on .NET 4.0, just type into Package Manager Console:
PM> Install-Package EntityFramework -Version 188.8.131.52