owner's manual.
http://www.southerntelecom.com/polariodsupport/downloads/PMP500.pdf
Tell us exactly what happens. Error messages? Also, maybe this player will only play specific video files. What type of files are you trying to play?
My son who Down Syndrome has a 2 hr bus ride to school. Bought the player because it looked simple enough to use and would keep him occupied by looking at movies and hearing music. I am having trouble importing movies. I'm a newbie in using this so I am not very knowledgable in what methods to take to properly import them. I've tried importing directly and also using a micro sd card but have been unsuccessful. Any suggestions?

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