I bought a SPI MP3 player at JC Penney. It won't sync to my WMP?

I charged it first then went to sync music onto it and it won't let me. I get an error saying that it cannot sync at this time or one that says my hard drive is full and to delete unneeded files. I have 52% free space on my hard drive!!! Did I get a defective MP3 player or is something wrong with my computer? I have no problem syncing songs onto my sons MP3 player from Walmart. Any ideas or thoughts would be greatly appreciated as I'm ready to throw everything out the dang window...I'm so frustrated over it!