Windows 64-bit registry v.s. 32-bit registry

Question

I heard on Windows x64 architecture, in order to support to run both x86 and x64 application, there is two separate/different sets of Windows registry -- one for x86 applica

Answer 1

How to register .NET assembly to be used as COM in pure 64-bit application?

Problem: By default, if you enable "Register for COM Interop" in build settings, it DOES NOT register type library for 64-bit.

Solution: To register your assembly which is not in GAC on a 64-bit machine, open cmd window and do:

cd c:\windows\microsoft.net\framework64\v2.x.xxxxx
regasm /codebase "path to your compiled assembly dll"

This will eliminate "Class Not Registered Error" when using native C++ to instanciate .NET assembly as COM object.