Please specify the exact text of the error message, word for word. And please specify exactly where this message is appearing. Is it on the player's screen, or is it on the Windows screen?

Also, you say the software is "the latest", but do you mean the latest alpha version (3.0 alpha) or do you mean the latest stable final version (2.0 final)?

Also, are you synching with USB or with ethernet, and what version of Windows are you using? If you're using USB and Windows XP, make sure to read the FAQ about how USB+XP is tricky and needs you to hand-install an updated USB driver.