5150Available in the U S only for the K-12 market starting fall 2014TroubleshootingDISPLAY PROBLEMSThe screen isunreadable ordistorted.n Make sure that:– The screen resolution and color quality arecorrectly set.–The monitor type is correct.Incorrect charactersappear on the screen.n Are the operating system or programs installedcorrectly? If they are installed and configuredcorrectly, have the computer serviced.SLEEP PROBLEMSThe critical low-batteryerror message appears,and the computerturns offn The battery power is getting low. Connect the ACadaptor to the computer.The computer enterssleep mode immediatelyafter power-on.n Make sure that the battery is charged.– The operating temperature may be too hot.Move to a cooler environment and try to wakethe computer.The computer doesnot return from sleepmode, and the computerdoes not work.n If your computer is in sleep mode, connect the ACadaptor to the computer, then press the Windowsbutton or the power button.n If your computer is powered-off, connect the ACadaptor to the computer, then press the powerbutton to resume operation.SOUND PROBLEMSNo sound can be heardfrom the speaker evenwhen the volume isturned up.n Make sure that:–The Mute function is off.–The combo audio jack is not being used.–Speakers are selected as the playback device.RECOVERY SYSTEM PROBLEMSFail to restore systempartition to factorydefaultn The system partition, such as the partition size orthe drive capacity of C, has been modified.OTHER PROBLEMSYour computerdoes not respond.n To turn off your computer, press and hold thepower button for 10 seconds or more. If thecomputer still does not respond, remove theAC adaptor.n Your computer might lock when it enters sleepmode during a communication operation.Disable the sleep timer when you are workingon the network.The connectedexternal devicedoes not work.n Do not connect or disconnect any externaldevice cables other than USB while thecomputer power is on. Otherwise, you mightdamage your computer.n When using a high power consumption externaldevice such as an external USB optical disk drive,use an external device power adaptor. Otherwise,the device may not be recognized, or the systemmay shut down as a result.TroubleshootingTroubleshooting