Depending on the MP3 player and the MP4 player you have, they may both be able to play or at least store the same types of files. It's a good idea to check what file types each player can play by looking on the box, but it's a good bet that both will be able to at least play MP3 music. You can transfer music or other files from one player to another using Windows Media Player.
Hook up your MP3 player to your computer with the USB cord that came with it. A window pops up asking you how to use the player. Click on the option to open with Windows Media Player.
Click on the "Sync" tab. You'll see your files on the MP3 player listed over on the left side of the tab. Drag them over to where it says "Drag files here" in the Sync tab. Click "Copy from device." Wait for this process to finish.
Unhook your MP3 Player and hook up your MP4 player with the USB cord that came with that player. A window will appear again. Open Windows Media Player once more, and click on the "Sync" tab.
Locate the files on your computer that you just added to your computer. You'll see the files listed under the "Library" text in the "Sync" tab. Drag them over to where it says "Drag files here" in the tab. Click "Start Sync" to transfer the files over.
- mp3 player image by patrimonio designs from Fotolia.com