iTunes could not back up the iPod because the iPod disconnected

I had and solved a problem similar to the one reported by others: My iPod Touch 5 would not back up to iTunes. I was trying to update the iPod from iOS 8.1.3 to iOS 8.2 using iTunes on my PC and iTunes needed to back up the iPod before installing iOS 8.2. All of the attempts ended with the error message, "iTunes could not back up the iPod 'username' because the iPod disconnected."

I was finally able to update to iOS 8.2 directly from the iPod using wifi rather than through iTunes on my PC but the iPod still would not sync/backup with iTunes. (iTunes version 12.1.1.4 running under Windows 7 Pro (64 bit) SP1.) I tried a soft reset on the iPod; powering down and back up the PC; restarting iTunes; disconnecting and reconnecting the iPod. Nothing helped (I did not turn off my security software). The "Backup now" command and the "Sync" command in iTunes both resulted in the same error message as given above. "Sync via wifi" was NOT checked in iTunes. The backup file in the PC was renamed "Backup-Old," forcing iTunes to start a new file, but that didn't help either.

Finally, I discovered that Backup/Sync DID work if I started the Sync from the iPod using the "Sync Now" command in "iTunes Wi-Fi Sync" under the "General" section of "Settings." After doing a backup once that way, the backup via iTunes worked properly. I don't know why it worked that way but obviously some block has been cleared. This method might be added to the list of "things to try."

Jeremy