cannot transfer files to mp3 player help please

I am using a samsung NC10 netbook on which i am trying to use my mp3 player.
Last week i returned a player thinking it was faulty and bought a different one only to have the same problem which is as follows.
When first plugged in the laptop recognises the player which requires no drivers as is drag & drop and tells me it is installed and ready to use. But when i try to either drag and drop or copy and paste i get "ERROR COPYING FILE" "THE DEVICE HAS EITHER STOPPED RESPONDING OR HAS BEEN DISCONNECTED".
The player works perfectly on my desktop PC which is also XP.
Any help on this would be most welcome as i want to take it on holiday shortly.
many thanks