63English EnglishTroubleshootingThis chapter shows you how to deal with common system problems.Read it before calling a technician if a problem occurs. Solutions to moreserious problems require opening up the computer. Do not attempt to openthe computer yourself; contact your dealer or authorized service centerfor assistance.Troubleshooting tipsThis notebook PC incorporates an advanced design that delivers onscreen errormessage reports to help you solve problems.If the system reports an error message or an error symptom occurs, see "Errormessages" below. If the problem cannot be resolved, contact your dealer. See"Requesting service" on page 46.Error messagesIf you receive an error message, note the message and take the correctiveaction. The following table lists the error messages in alphabetical ordertogether with the recommended course of action.Error messages Corrective actionCMOS battery bad Contact your dealer or an authorized service center.CMOS checksum error Contact your dealer or an authorized service center.Disk boot failure Insert a system (bootable) disk into the floppy drive(A:), then press to reboot.Equipmentconfiguration errorPress (during POST) to enter the BIOS utility,then press Exit in the BIOS utility to reboot.Hard disk 0 error Contact your dealer or an authorized service center.Hard disk 0 extendedtype errorContact your dealer or an authorized service center.I/O parity error Contact your dealer or an authorized service center.Keyboard error or nokeyboard connectedContact your dealer or an authorized service center.Keyboard interfaceerrorContact your dealer or an authorized service center.Memory size mismatch Press (during POST) to enter the BIOS utility,then press Exit in the BIOS utility to reboot.