[. . . ] Electrostatic Discharge (ESD) Static electricity, a normal and natural phenomenon, builds up on your body as you walk around. You experience an electrostatic discharge (ESD) when you touch an object and feel a spark. [. . . ] Avoid walking around while performing this procedure, and follow the instructions carefully when you are asked to discharge static electricity. Shut down your computer, remove the expansion bay modules, and disconnect the power adapter. Warning : Always turn off your computer before opening it to avoid damaging its internal components. If you have been using your PowerBook, wait 30 minutes after shutting down your computer to let the internal components cool down before continuing. Place your index fingers inside both expansion bays to locate the keyboard latches. The ribbed keyboard latches are located on the underside of the top case, just below the bottom edge of the keyboard. Operating the computer when it is open or missing parts can damage your computer or cause injury. Replacing International Modems After you have replaced a modem in Europe or Asia, open the software utility Modem Country Selector and verify that the modem is set to the correct country. Modem Country Selector is located in the Apple Extras folder on your hard drive or can be downloaded as part of the Apple Modem Updater software bundle at http://asu. info. apple. com. Apple Computer, Inc. Under the copyright laws, this document may not be copied, in whole or in part, without the written consent of Apple. The Apple logo is a trademark of Apple Computer, Inc. , registered in the U. S. Use of the "keyboard" Apple logo (Option-Shift-K) for commercial purposes without the prior written consent of Apple may constitute trademark infringement and unfair competition in violation of federal and state laws. [. . . ] The Apple logo is a trademark of Apple Computer, Inc. , registered in the U. S. Use of the "keyboard" Apple logo (Option-Shift-K) for commercial purposes without the prior written consent of Apple may constitute trademark infringement and unfair competition in violation of federal and state laws. [. . . ]