Computer wont read mp3 player when connected

Question

When i plug my mp3 player into the computer with the usb cord or w/e it lights up and says ready on the screen of the mp3 ..but it doesnt connect on the computers end...it doesnt read/load it at all when i try to synchronize music onto it from windows..it says no device detected...i only have 190 songs on it and it can hold up to 400

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