ipod touch will not sync after new itunes update

Ipod touch 4th generation will not sync after I updated the new itunes. Actually after I updated to the new itunes it deleted all my music from my ipod and refuses to reload. If someone could please help me that would be completely appreciated. I tried trying to sync each song individually but it didn't help (before it stopped syncing), then it stopped syncing, even though I have it hooked up it brings everything that I have on my ipod up but it won't do anything.