Problems with synching IPad to Itunes

I plug in my Ipad into my USB on my computer to synch with Itunes. This ALWAYS worked in the past. My Nano still works this way.

With my IPad, the computer and Itunes picks up that it is plugged in and starts to Synch. However, it does not finish synching as I get this error message: "... the connection to [my] Ipad was lost"

I have rebooted my computer and my Ipad, tried different USB ports and different cables (all genuine and purchased from Apple). I still get the same error message. Please help.