I have just bought a new MacBook Pro with retina display today At the moment in my current macbook pro, I have got a 1TB hard drive, most of this space is taken up by my music collection which is about 550GB. I bought the base model rMBP, so only have 256GB storage. I was going to do a simple time machine back up and then restore to my new macbook. I am trying to reduce the space used on my HD so I have bought an external hard drive, and am planning to move my music collection onto there. However when I do this, there is an exclamation mark next to each song in iTunes. The obvious solution would be to delete all my music in iTunes, and then transfer it back once it is copied to the hard drive. But then I would lose all the data like date added, date played, ratings, play count etc. Is there a way I can transfer the music to my external HD, but still keep all the data in iTunes like the play count, date added etc?