Whenever a hard drive is lost — whether it’s to a crash, accidental deletion, or theft — it’s a big problem. You lose data, some of it sensitive, one-of-a-kind items like photos, and things that you’ve bought as downloads, such as music purchased from the iTunes Store. If this has happened to you, you're probably wondering how to recover iTunes after a hard drive crash or theft?
Appeal to Apple
Use a Backup
Good computer use includes making regular backups of important data on your computer. It’s not something all computer users do, and it can be a hassle, but it pays dividends in these cases.
If you’ve got a backup, you can restore your iTunes library (and other content) from it when you get a new or repaired computer. If you don’t have a backup, start making regular backups with your new machine.
Use an iPod Copy Program
As long as your iPod has all of your purchased music on it, you can get it back. Purchase an iPod copy program and use it to copy the contents on your iPod onto your new or repaired computer (do this before you install iTunes on the new hard drive to prevent erasing your iPod).
Once the music is copied from your iPod, it will be on your hard drive again and ready for use. You’ll need to authorize your new computer to play purchased content from the iTunes Store.
If Stolen, Deauthorize
If your computer is stolen, you’ll want to try to deauthorize that machine to play purchased iTunes Store content. Remember, iTunes DRM limits your account to just five computers authorized to play your music, so if you don’t deauthorize the stolen machine, you’ll have one less authorization to use.
Normally deauthorization is done through iTunes on the machine you want to deauthorize. But, since that machine is now gone, contact iTunes Support, explain the problem, and they should be able to help.