*I can first confirm that it isn't 6.4.09.1121, Linda.*  On an XP box, if
you pop "mplayer2" into the run box, up will pop your friendly 6.4.09.1130
that comes in Windows XP as part of the "antiques from Redmond" wing of that
OS.   If you pop "wmplayer" in, you'll get whatever version of WMP you're
using, and if on Thursday, you download the new WMP 10 that's released along
with Microsoft's answer to IMusic, you'll get WMP10.something.  If you type
in "media" you'll get the folder of wave sounds.  If you go here you can
click  Media Player Classic 6.4.8.2 and 6.4.5.6 shows up but I'm  not sure
if MSFT made this one.
http://www.softpedia.com/public/scripts/photohero/11-2-1-42/

I tried to find you a clean list of *all* the WMPlayers, but I'm still
looking.  I did find links with a little bit of history, and maybe the boys
and girls from MSFT can come up with a comprehensive, complete list.
http://support.microsoft.com/default.aspx?scid=%2Fservicedesks%2Fwebcasts%2Fen%2
Fwc071300%2Fwct071300.asp

http://en.wikipedia.org/wiki/Windows_Media_Player

http://www.updatexp.com/windowsxpmediaplayer.html

I am trying to determine what was the latest release of
Windows Media Player 6.4?  I don't think it was
6.4.09.1121.  Can anyone confirm what the latest is?