When you connect an Apple iPhone, iPad or iPod to a new computer and attempt to transfer purchases from the device to iTunes, you will often get prompts for an Apple ID and Password. These prompts appear because iTunes has to verify that you are the rightful owner of the music on the device before importing it. This prevents a thief from stealing your device and importing music onto their own computer. It also prevents piracy.
To successfully import all of the music from your device, you must enter the Apple iTunes Store account that was used to purchase each music file. Because of this, you may be prompted several times for different credentials. If several family members used their own Apple iTunes accounts to purchase music on the previous computer you synced your device with, this can be quite a confusing process.
To make things easier, keep in mind that the Apple ID associated with each music file will be automatically filled in when prompted. Don’t try to change the Apple ID and use other credentials. It won’t work. You must provide the password associated with the pre-filled Apple ID if you wish to import the music files successfully.
You may need to get the owner of each song to enter the password for you. If you can’t enter the password for a file, you won’t be able to import it and it’s gone for good.