TUTORIAL Don't know if you've noticed, but 64 bit versions of Windows 7 not only come with a rather useless 64 bit version of Internet Explorer these days, but also a well-hidden Windows Media Player 12, running in 64 bit. The 32 bit version is used by default, however. Here's how to switch over to the x64 version!

As mentioned, Windows insists on using the standard 32 bit version of WMP even if your OS runs in 64 bits (of compatibility reasons, presumably). Until you tell it otherwise, that is.

The highly desirable 64 bit version is nowhere to be found in the "Start" menu, so no point looking there. Instead you'll have to do it the good old way, by opening a file explorer window (Windows key + E) and browsing to the "Program files" folder - or more specifically:

[Windows install drive, usually "C"]:\Program Files\Windows Media Player\
(As opposed to X:\Program Files (x86)\Windows Media Player\, in which the 32 bit version is found.)

Once there, run the .exe file wmplayer.exe which (unsurprisingly) boots up the 64 bit version of WMP.

Run Windows Media Player in 64 bit by default

Pardon the Swedishness.
If you want to run the 64 bit version by default, there are some more or less cumbersome approaches, that involve some fiddling with the Windows registry (read Shinmila's post in this thread). A far simpler approach, however, would just be to re-route all your shortcuts to from the 32 bit version to the 64 bit one, either by Alt-dragging new ones out, or by right-clicking the WMP icon, then choose Properties... Then alter the field "Target" from Program Files (x86) to simply Program Files, without the " (x64)" in the directory path.

Then do the same with any file formats you want to open with WMP x64;
Right-click a file you want to open and again choose "Properties...". Where it says "Open with", hit the button "Change", followed by "Browse..." from the pop-up window. Then all you have to do is to direct it to the 64 bit version of WMP, usually found at C:\Program Files\Windows Media Player\wmplayer.exe

Repeat this with all file types you desire to open with the 64 bit version.

Have fun with it, kids!
/theJo

See also