IPod won't sync because of unknown error

Hello,
I've had the iPod nano since Christmas of 2009, you know, when they just came out with the camera built in. So it was brand new when i got it. Since a week ago, on my iPod it says "connected", but on the itunes library sreen on my computer where i try to sync the iPod to put more songs on it, it just says "The iPod 'Nathaniel' cannot be synced. An unknown error occured." While it says this, my iPod is saying that it is syncronizing, but the new songs aren't put on the iPod. I really don't understand what the problem is. I have dial-up, but it's been working all this time with it, and it's worked just fine with out an update, since i've only had the same itunes for 1 full year... So is there anything else that i can do? Anything I've overlooked or haven't checked into? i just really want to avoid updating with the dial up. Please please PLEASE help me.

Thanks so much,

-MDC