Back up the purchases from the iTunes library on your current computer or your iOS device, then set up your new computer so that it is authorized to house your iTunes library. Most iTunes library purchases are available on up to five separate computers.
- Back up your iOS purchases
Sync your iOS device with iTunes on your current computer. This ensures all your purchases and all downloads are accounted for when you sync the iOS device with iTunes on the new computer.
- Connect the device
Insert the USB cord of the iOS device that includes your iTunes library into the USB port of the new computer.
- Authorize the new computer
Open iTunes on the computer to which you want to transfer your iTunes library. Click Store in the menu at the top of the screen, then choose Authorize Computer. Click Authorize.
- Transfer the purchases
Click on the device icon at the top of the screen to make sure the proper iOS device is selected, then choose File. Next, click the Transfer Purchases button.
- Give the device time to sync
Wait as the iTunes library syncs with the new computer. This process could take several minutes. Once the sync concludes, remove the USB cord.