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If you have obtained a .rm file, then you have a Real Media file. These files are intended to be used for streaming content over the Internet. However, while Real Media is still in wide use, newer streaming options beat it hands down for quality. Real Alternative is a good player for Real files. You can also try Media Player Classic.
IMPORTANT</B>: These instructions are a few years old. However, we have a newer, more detailed and eloquent set of instructions for RM / RMVB files in our Guides section. Click here to read our proper [b]How to play RM and RMVB files article.
Download Media Player Classic from: http://www.afterdawn.com/software/video_software/video_players/media_player_classic.cfm
Download Real Alternative from: http://www.afterdawn.com/software/video_software/video_players/real_alternative.cfm