X86

When migrating to 64-bit Windows, traditional “unmanaged” applications can pose challenges. That is because unmanaged binaries contain hardware-dependent CPU instructions - and the view on the hardware differs between 32- and 64-bit mode. But .NET? It should be unaffected of a system’s bitness since “managed” binaries contain instructions in a so-called intermediate language that is executed in a virtual machine at run-time and only then translated to machine language. But is it really? This article is about .NET programs that are dependent on OS bitness.

At the verge of the transition from 32-bit to 64-bit Windows it is interesting to observe how people interpret and misuse acronyms for the definition of “their” platform. Looking at the acronyms in use out there one might consider oneself back in the eighties, with dozens of different incompatible computer systems. Unfortunately it is more boring than that. Let’s have a look.