mp3 wont take new songs

[Alltrades]

Hi,
I Have a 32 gig mp3 player. I have put about 1800 songs (about 5 gig) on it into different folders. All of them from my computer and they are all working. I have a problem now that I copy or drag songs across, even ones that I have already put there to test them. They will not play either while connected to the computer or through the player when by itself. If I try to play while connected the windows media play does not recognize the file. When I try to play music through the mp3 player when disconnected, I can play the older ones I have put on but cant get into the new folders. now that I have tried the new folder I cant play any of the older ones unless I exit to the menu. when I connect back to the computer I find the folders are there still but all the mp3 files from the new ones have gone, yep Gone. Its got me a bit beat. I'm thinking it may be the mp3 player.
Would certainly appreciate any helpful thoughts.
Cheers
ken

 

[Alltrades]

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Question from Alltrades : "New files wont show or play on mp3 player"

Hi,
pretty new at this so don't even know if this will post so wont go into to much detail yet. basics are that I have 32 gig mp3 player, have put about 1800 songs in different folders. they all play through the player or through windows media player when connected but new files copied or dragged wont play either way. media player does not recognize the file. Once it has been tried to play on the mp3 player it will not work and when connected back to computer, the folders are there but the files are gone. can any one suggest anything as its got me stumped. im thinking there is a problem with the mp3 player. Thanks