I'm currently using the x64 version of the Vista Codec Pack: Vista Codec Package Homepage
I've used the tools it provides to set Windows to use Media Player x64 as the default. All registered media files, such as AVI, MP3, MPG, etc, open in WMP x64 when double-clicked. If I use the shortcuts on Quick Launch or the Start Menu, WMP x64 starts.
However, when I use the media keys on my keyboard to launch Media Player, the x86 version of WMP is launched. I do not have any drivers installed for my keyboard, other than the generic driver provided by Windows Vista x64, so the media keys are handled by Windows.
How do I set Windows Vista to open Windows Media Player x64 when I use the "Launch WMP" key on my keyboard? All methods other than this one will launch WMP64.