28 TroubleshootingSystem MessagesNOTE: If the message you received is not listed in the table, see the documentationfor either the operating system or the program that was running when the messageappeared.Message Possible Cause Corrective Action8042 Gate-A20errorThe keyboardcontroller failed its test.If you receive this messageafter you make changes inthe system setup program,enter the system setupprogram and restore theoriginal value(s).Address LineShort!An error in the addressdecoding circuitry inthe memory hasoccurred.Reseat the memorymodules (see the ServiceManual on the Dell Supportwebsite atsupport.dell.com).C: Drive ErrorC: Drive FailureThe hard drive is notworking or is notconfigured correctly.Ensure that the hard driveis installed correctly in thecomputer and definedcorrectly in the systemsetup program (see theService Manual on the DellSupport website atsupport.dell.com).Cache Memory Bad,Do Not EnableCacheThe cache memory isnot operating.See "Contacting Dell" onpage 54 for instructions onobtaining technicalassistance.CH-2 Timer Error An error is occurring onthe timer on the systemboard.See "Contacting Dell" onpage 54 for instructions onobtaining technicalassistance.