No license to play. sync license from PC

If you are using a subscription service, Rhapsody, or other, you need to sync the device to the service to verify your account and renew your licenses. Generally every 30 days. If this is not the issue then you have used your own cd's and used Windows Media Player to copy your music to your computer. By default Windows Media Player "copy protects" your music. You would need to change the setting in Windows Media Player. Under Tools>Options>Rip Music or Copy Music Tab, the un-check the "copy protect my music" box. Then you will need to re-transfer the cd's to your PC, and re-transfer the music to your device. Make sure you delete all of the previously transferred music, or you will always receive an error. Please add to this question for additional assistance. Best of Luck.