These errors appear whenever I right click a *.tt file and select Run Custom Tool in Visual Studio 2012 update 3.
Compiling transformation: The type or namespace name 'CSharp' does not exist in the namespace 'Microsoft' (are you missing an assembly reference?)
Compiling transformation: The type or namespace name 'CSharpCodeProvider' could not be found (are you missing a using directive or an assembly reference?)c:\Program Files (x86)\Microsoft Visual Studio 11.0\Common7\IDE\Extensions\Microsoft\Entity Framework Tools\Templates\Includes\EF.Utility.CS.ttinclude
Compiling transformation: The type or namespace name 'CompilerErrorCollection' does not exist in the namespace 'System.CodeDom.Compiler' (are you missing an assembly reference?)c:\Program Files (x86)\Microsoft Visual Studio 11.0\Common7\IDE\Extensions\Microsoft\Entity Framework Tools\Templates\Includes\EF.Utility.CS.ttinclude
These same templates work for other developers in my group who have basically the same development environment, so it's probably something misconfigured or incorrectly installed on my computer.
I've tried uninstalling and reinstalling VS 2012 as well as Update 3.