You have checked the wrong registry branch !!! You have to check the 32-bit branch, not the 64-bit one ;-)

If you see "{8785CD50-6DA8-11DB-3D6C-1A86F5694AE1}" under HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\Curr entVersion\Uninstall on your 64-bit OS then this was a 64-bit install.

32-bit apps are registered here:

HKEY_LOCAL_MACHINE\Software\WOW6432node\Microsoft\ Windows\CurrentVersion\Uninstall

It works 100% Millions of installs are doing this !!! Please note that a 32-bit install will not detect your previous (hybrid) installed product because a hybrid install is done in 64-bit mode on x64 machines. So only a 64-bit mode installer can detect your 64-bit enabled install. 32-bit and 64-bit apps are completely different animals.

BTW, if you need a simple example, just let me know.

Friedrich