To Sync up SharePoint data with AD you need to synchronize the
user profiles.
Refer to related links.
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'Sync' with 'iTunes', When you 'Sync' It backs up all your Data
to 'iTunes'.
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If it is an ipod you can just sync it with itunes.
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The very word 'sync' means it goes BOTH ways. Your iPhone data
will be copied over to your computer, and your computer's data will
be copied the other way. Sync is short for 'synchronise' which
basically means swap/exchange.
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Unfourtunately, you can't, you will have to reenter the
data.