Background:

I run Vista Ultimate x64 (64-bit).

Message:

When I open the Windows Photo Gallery, I am told that, "An Update to Windows Photo Gallery is Available".

Sure.  Sounds good to me.    If I choose to download the update, I'm directed to a Canon page, which looks like this:

Discussion:

So the 64-bit version is not supported.  Lovely.  Someone botched the 3rd party software integration.

If the app was written in-house, then it would already have been ported to 64-bit, be localization-ready, undergone a security review, etc. Because those are basic ground rules for coding at Microsoft.

http://blogs.msdn.com/oldnewthing/archive/2008/02/25/7885570.aspx