Subject: bug#14794: 24.3.50; `w32-register-hot-key' does not work on Windows 7 64-bit

From: Eli Zaretskii <[email-masked]>
Date: Wed, 10 Jul 2013 20:19:14 +0300

> Date: Thu, 4 Jul 2013 14:10:45 -0700 (PDT)
> From: Drew Adams <[email-masked]>
> 
> At least it does not work as far as I can tell.
> 
> emacs -Q    ; but same problem with older Emacs versions
> 
> (w32-register-hot-key [M-tab])
> (w32-register-hot-key [M-S-tab])
> 
> Try C-h k M-TAB.  Try M-TAB.  The key is immediately grabbed by Windows. 

Because it is not bound to any command.  If you bind it, it will work
as expected.