I’ve already forgotten this tidbit once.  So now I am making this note both to myself, and to maybe help someone on the entirewebs.

If your iPhone refuses to sync or backup through iTunes, it is likely due to one of two causes:

1. The iPhone itself is actually having a problem.  (I have not encountered this, personally.)
2. There is something screwed up with the USB port you have it plugged into.

This can be a temporary software issue (as can happen when you unplug a device without officially removing it in Windows).  But can also be an actual problem with the physical USB port.  I have had both happen.

At first, after researching this problem with the knowledge floating around the web, I thought it was a problem with one of the applications, or of too many applications, etc.  While it is true that removing all your applications may make this problem go away, I’m pretty sure it wasn’t the applications that had the problem, but that there was more data being transmitted through the USB port that was wonky, and therefore the issue had more chances to rear it’s ugly head.

My solution to you, is to first try to relocate the iPhone USB cable to a new USB port,  and then try again.  But most importantly, because it is usually my problem, and I always forget:

Use a USB port that is directly attached to your motherboard.

It seems the iTunes helper dlls or whatever, that regulate communication between your Apple wonder and your system, are prone to stutter at most any wonkiness.  Sometimes, if there is the smallest of hangups in your USB hub, it will simply kill the entire transaction and spit out error messages that make it sound to you as if your iPhone is kaput.  Thank you, Apple, for learning such descriptive error messages from Windows 3.1.

fin.