While most media players, even in 64-bit operating systems, use 32-bit media players by default, there are a few 64-bit players around. To make use of every media format out there, you'll need a codec pack, and K-Lite Codec Pack 64-bit Edition has everything you'll need.

When installing K-Lite Codec Pack 64-bit Edition, you choose which components you want which is great, as long as you know what that is!
If you're not really sure what a codec is, or what you need, the installer won't help you. However, a solution to this is to simply install them all!

There is little demand for a 64-bit set of codecs at the moment, but as 64-bit systems become more common place, K-Lite Codec Pack 64-bit Edition will become more useful.
Be aware that by default, 64-bit editions of Windows still use 32-bit media players, in which case the K-Lite (Mega) Codec Pack should be used.

Download K-Lite Codec Pack 64-bit Edition 9.5.5 in Softonic