Mac OS X
- Close iTunes
- Move the existing ~/Library/Application Support/MobileSync/Backup/ folder to the destination drive (for example, named BigExternalDrive)
- Open a command prompt by launching Terminal and create a symbolic link using a command similar to the one below, replacing /Volumes/BigExternalDrive/Backup with the path to your destination:
ln -s /Volumes/BigExternalDrive/Backup/ ~/Library/Application\ Support/MobileSync/Backup
Windows Vista and Windows 7
- Close iTunes
- Move the existing C:\Users\(username)\AppData\Roaming\Apple Computer\MobileSync\Backup\ folder to the destination drive (for example, D:\)
- Open a command prompt and create an NTFS junction point using a command similar to the one below, replacing D:\Backup with the path to your destination:
mklink /J "C:\Users\(username)\AppData\Roaming\Apple Computer\MobileSync\Backup" "D:\Backup"
Windows XP
- Close iTunes
- Download and extract this junction utility to your Desktop
- Move the existing C:\Documents and Settings\(username)\Application Data\Apple Computer\MobileSync\Backup\ folder to the destination drive (for example, D:\)
- Open a command prompt an NTFS junction point using a command similar to the one below, replacing D:\Backup with the path to your destination:
cd Desktop
junction "C:\Documents and Settings\(username)\Application Data\Apple Computer\MobileSync\Backup" "D:\Backup"
