Summary: You can only use this drive with its Safe Manager. I got it to use with Time-Machine on a MacBook Pro. For the initial backup I calculated it will take five days. I went to my USB drive and did the initial Time-Machine back up in less than five hours. This is NOT the external drive you would like to have with a laptop. Who runs their laptop for five days without shutting down? It also took half an hour to delete three files of 2.5 GB. Soooo Slow!