I'm unable to sync contacts because of an error "pushing data" to my iPhone, what can I do?
If you're having a problem syncing your contacts to/from your iPhone and are receiving a message that indicates an error occured while pushing data to the iPhone, here is a possible fix:
Open Finder and run iSync from the Applications directory. Select Preferences from the iSync menu and hit the "reset sync history" button.On Windows:
Open iTunes and choose Edit -> Preferences. Select the Sync tab and choose to reset sync history.
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This has been shown to resolve the "pushing data" error for most people.