Below is the location of the iPhone and iPod MobileSync Backup Files That iTunes creates during a sync
Mac OS X
iPhone: ~/Library/Application Support/MobileSync/Backup/
iPod touch: ~/Library/Application Support/MobileSync/Backup/
(The tilde “~” represents your Home directory. If you don’t see Library in your Home folder, hold Option and click the Go menu.)
Windows XP
iPhone: C:\Documents and Settings\[username]\Application Data\Apple Computer\MobileSync\Backup\
( To quickly access the Application Data folder, click Start, and choose Run. Type %appdata% and click OK.)
iPod touch: C:\Documents and Settings\[username]\Application Data\Apple Computer\\MobileSync\Backup\
Windows Vista, Windows 7, and Windows 8:
iPhone: \Users\(username)\AppData\Roaming\Apple Computer\MobileSync\Backup\C:\Users\[username]\AppData\Roaming\MobileSync\Backup\
iPod touch: C:\Users\[username]\AppData\Roaming\MobileSync\Backup\
(If you don’t see the Application Data or AppData folders, you may need to show hidden files.)
To quickly access the AppData folder, click Start. In the search bar, type %appdata% and press Return.
More info from Apple in HT4946
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