Dennis has an old iMac from 2006 and he's having problems getting it to boot up. How can he move files from the old Mac to his new Mac? Leo says that there's a utility option called "Target Disk Mode." Press and hold "T" on startup and it'll put the Mac into Target Disk Mode. This means the Mac will appear as an external hard drive to the computer it's connected to. He'll need to get a FireWire 800 to Thunderbolt adapter to connect the computers, though, and he can pick one up for $30 from Apple.