anybody can help me to convert the rmbv to video file? 
rmvb IS a video file (real media variable bit rate). I’m guessing your problem is one of these two:
1. You can’t play the file. Get real player or real alternative (recommended). http://home.hccnet.nl/h.edskes/finalbuilds.htm (scroll down)
2. You can play the file, but you want to convert it to a different format. Real Media is a proprietary format and I can’t think of any program that will convert it to another format off the top of my head. (If you find one, post in thread 3459; the guy there is looking for such a tool too. http://www.moviecodec.com/thread/3459.html)
How can I play a movie with rmbv file ???
rmvb video can be played by realone player.
If you want to convert video format on Mac, you can turn to mac video converter.
Hope it helps.