You Mac users virtualizing Windows with Parallels can expand XP’s C: drive size using the free GParted Live CD. While Parallels’ Image Tool can expand your virtual hard drive, the free space the Image Tool creates must be “contiguous”—right next to C:’s used space—in order to expand C:. That’s where GParted comes in. Parallels user Declan runs down the steps of how to enlarge the C: drive using a live CD virtual machine. Whatever you do, make sure you back up your Parallels images before you start.