text: what player do i need to play mms files? i cant play mms file on media player.can some one tell me what i'm doing wrong? is there a player that will play them? thanks there is no such file format.  mms is microsoft media server (mms) protocol which is for streaming media over the web.  microsoft says: "to play content that uses the mms protocol, start the player, and on the file menu, click open url, and then type the url."