Introduction The official answer is you can’t. Even with the In-Process Side by Side execution (SxS) feature, introduced in .NET 4. The SxS feature was intended to be used when COM is involved. For example, if you got an application that loads plugins, like outlook, and it loads 2 COM plugins, one is using .NET 4 and the other is using .NET 2.0 then it will load two versions of the CLR into the process using the new SxS feature. What if I simply have a .NET 2 application or DLL that needs to access...