A Bad Desktop File: The Mac maintains an invisible file that keeps track of things like what programs have what icons, what documents go with what programs, etc.. This file is called “Desktop.” If it goes bad, document icons can begin to switch to plain icons and other problems can result. To rebuild the desktop file on a hard disk, hold down the Command and Option key while restarting the computer. Comments entered into the little box that appears when you “Get Info” in the Finder are lost.
