iTunes won't sync my purchases to my iPhone

I'm having an issue with my iPhone where iTunes won't sync any purchased music to it. The songs sync just fine to my iPod touch, but the iPhone always says "102 items could not be synced. Please see iTunes for more information." Of course, when I switch over to iTunes there is nothing there with any information. All 102 songs are purchases from the iTunes Store, and as I said before, sync just fine to my iPod touch. I have deauthorized and reauthorized my computer several times to no avail. Any help here would be greatly appreciated.