Detect whether Office is 32bit or 64bit via the registry

Question

Now that Office also comes in a 64bit install, where in the registry do you find out if the version of Office installed is 32bit or 64bit?

Answer 1

I've previously blindly followed the answer based on the MSDN docs. Today, this turned out to be less than required. On a machine with Office Home and Student installed, which doesn't include Outlook, HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Office\14.0\Outlook was present, but HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\14.0\Outlook was not. I've now changed my code to first look for the "plain" non-Wow6432Node version. If that's present, it'll be used. If not, it will continue by looking at the Wow6432Node version. This is being checked in an Inno Setup-based installer - I don't know which APIs Inno Setup uses. If your app doesn't access the registry in the same way, you might see different results.