I created a WiX installer deploying an add in for Windows 2010. Target system is currently x64 Win & Office installed. I walked through several microsoft sites telling m
On x64 systems WoW64 apps are transparently redirected into Wow6432Node
node of the registry, so they actually look for a key like HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\VSTO Runtime Setup
there it is located. But the real x64 apps look into real HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VSTO Runtime Setup
node, and the key is, naturally, not present there. This, most probably causes your installer to fail. So, for a x64 installer you need to specify full node with Wow6432Node
path part.
This is called Registry Reflection and covered in details here.