At some point, we believe everyone has experienced this error message during a sync between iTunes and your iPad or iPhone (Apple still has some polishing to do for iTunes).
Despite repeated syncs, usually, the error repeats.
There are 2 steps to take to remedy this:
- Hard reset your iOS device – hold down both the power and Home button until the iOS device restarts (attempt a fresh sync after the iOS device has restarted) and/or;
- Reset iTunes sync services
The second step described above is slightly more complicated since Apple did away with the legacy iSync app in 2011. Previously resetting sync services only entailed clicking on a menu item however since iSync’s demise, use of the Terminal app is required (/Applications/Utilities/Terminal.app).
This process requires different Terminal commands depending on the version of OS X you are currently running.
Details can be found at Apple’s OS X: Resetting Sync Services support knowledge base article.
The above can also be used to address the dreaded “session could not be started” syncing issue as well.
If however, all of the above steps still fails to address the issue, the final resort is to restore your iPad/iPhone.