Sync problems

Apple iPhone - Sync problems

I am trying to sync my wife's 3G iPhone on our Mac. A message pops up after the 3rd step , stating "unable to sync iPhone, file missing". No idea or information about what file? I have restored the iPhone with no issues and when I went to sync again the message appeared again. Any thoughts or suggestions are welcome.
iPhone Sync
I had that same message with my wife's iPhone4 yesterday on my PC. I tried a number of times and got the message. I then re-booted the PC and it then completely synced. Don't know why that happened, but it has happened to my phone as well a few times over the past several months.

I know this doesn't help your situation, but I thought I should let you know that others are having similar problems.

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I don't have a mac but something similar happened on my PC. When I deleted the old backup and made a fresh new backup the error disappeared. Not sure if it will work for you.