Windows XP support has been dropped. Since attempts to talk sense into XP users are generally futile, I’ll just link the last build that works with it here.
These are built from the current releases, except for some dependencies like libass and FFmpeg (which are built from Git master). The “Dev” archives contain debug symbols and libmpv for both architectures.
To set up file type associations and AutoPlay handlers, use mpv-install.bat.
To play content from various media streaming sites, place youtube-dl.exe in the same directory as mpv.
If you notice anything wrong with these builds, complain in #mpv on Freenode or report the problem on the issue tracker.