A media player is presented that scans the media files stored on an external memory card in order to update the internal database of the player. Media manager software on a personal computer sets a dirty bit in the internal memory of the media player whenever the media files on the external memory card are altered. The media player checks the dirty bit on start up or when the memory card is inserted. If the dirty bit is set, the media player scans the media files on the memory card, updates its database, then clears the dirty bit. If the dirty bit is not set, the media player does not scan the memory card. The dirty bit is associated in the internal memory with an identifier for the memory card, allowing the use of multiple memory cards.