(2) Windows 32-bit and 64-bit Registries
A 64-bit Windows computer has two completely separate registries.
There is a 32-bit registry, and a 64-bit registry.
32-bit applications see the 32-bit registry, whereas 64-bit applications see the 64-bit registry.
A 32-bit ActiveX DLL must be registered in the 32-bit registry.
A 64-bit ActiveX DLL must be registered in the 64-bit registry.