C150 pls sync to listen to tracks

Hi, Newbie on this so bear with me. Have always bought sansa many times. I am getting a “please sync your devise to listen to tracks” I have searched forums but cannot find answer. Have been at it for the last 4 days and getting frustrated. Can anyone help, step by step, since I’m not getting it? Thanks is advance,

Dizzy

your getting that message becuase of a conflict with licenses on the songs.

where did you download your songs from?

how did you transfer them to the device?

did it previously work fine, if so, for how long?

is your computer winXP?