To charge the RTC battery, connect the AC adapter and turn the computer on (both the DC IN and Power LEDs must be green). Charge the Real Time Clock (RTC) battery.Set the correct date and time, then click OK to save. Open the Windows Control Panel and open the "Date and Time" control by double-clicking its icon. Go ahead and click "OK" to clear the error dialog. Set the correct date and time in WindowsĪs Windows starts-up, you may see an error message about an "Invalid System Time".In the BIOS setup screen press the key to restore the default values, then press the key to save and exit, then the key to confirm and restart the system.Press the key as instructed in the error message:.Please follow the detailed instructions in the next section. Set the correct date and time in Windows.This condition is easy to fix in 3 basic steps:
#CMOS CHECKSUM INVALID UPDATE#
Other symptoms include not being able to execute Windows Update properly, errors/problems executing application software (like Norton Antivirus), and the appearance of the Windows XP "Desktop Clean Wizard". This error can occur when a machine has been left turned-off for an extended period of time ( approximately one to four months), and it is the result of a depleted RTC battery. The Real Time Clock (RTC) battery provides power for the internal clock/calendar and for maintaining system configuration settings. When you turn your Toshiba computer on, you see an error message like: