You need to use windows media player to rip it into an mp3. Then transfer the files to your media card. All of the itunes songs in my gf's computer have played in my bb with no problems. Limewire files play fine also.
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If you have Mass Storage Mode enabled you don't need to use DM. Just open the bb as removable drive (disk), open the musica folder and drag and drop all at once.
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