Reader Mary R. has reformatted the hard drive and reinstalled Mac OS X on an old machine she wants to sell and asks, "In the process of reinstalling Mac OS X, I had to enter my personal data. Where does this information reside? I would like to update it when I sell the Mac."

The personal information for the default account created when you install Mac OS X goes into the Address Book on the My Card card. To get to that card, open Address Book and choose Card > Go to My Card.

—Posted by Michael E. Cohen on November 8, 2010