Dormant Laptop Startup Query

  Mike43 11:58 07 Sep 2006

I've found a use for an old Toshiba Satellite 21OCT which has been out of use for some years. It runs ok, but on startup it shows this message - "Bad RTC battery, Bad Check Sum (CMOS), check system then press F1"

F1 brings up the System Setup screen, and exiting this starts Win 95 which is fine but the clock etc is always reset to 00:00

Is this a problem I can sort with a new battery? I have no manual now and the Tosh website doesn't support this model any longer.

Any help much appreciated.

  SANTOS7 12:06 07 Sep 2006


When you turn your Toshiba computer on, you see an error message like:

**** Bad RTC battery ****
**** Bad Checksum (CMOS) ****
Check system, then press [F1] key

The Real Time Clock (RTC) battery provides power for the internal clock/calendar and for maintaining system configuration settings.
This error can occur when a machine has been left turned-off for an extended period of time (around a month), and is the result of a depleted RTC battery. 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 condition is easy to fix in 3 basic steps:

Reset the BIOS defaults
Set the correct date and time in Windows.
Charge the RTC battery

Please follow the detailed instructions in the next section.


Set BIOS defaults

Press the [F1] key as instructed in the error message:
**** Bad RTC battery ****
**** Bad Checksum (CMOS) ****
Check system, then press [F1] key

In the BIOS setup screen press the [Home] key to restore the default values, then press the [End] key to save and exit, then the [Y] key to confirm and restart the system.

Set the correct date and time in Windows

As Windows starts-up, you may see an error message about an "Invalid System Time". Go ahead and click "OK" to clear the error dialog.

Open the Windows Control Panel and open the "Date and Time" control by double-clicking its icon. Set the correct date and time, then click OK to save.

Charge the Real Time Clock (RTC) battery

To charge the RTC battery, connect the AC adapter and turn the computer on (both the DC IN and Power LEDs must be green). Leave the machine on for approximately 24 hours to ensure a full charge in the RTC battery. Please note that the RTC battery does not charge while the PC is turned off, regardless of whether the AC adapter is connected or not.

Other Information:

If, on subsequent reboots, the "Bad RTC Battery" error persists, it's quite likely that you actually do have a bad RTC battery. If that's the case, you should contact a Toshiba Authorized Service Provider to have the system serviced.

Windows XP Desktop Cleanup Wizard

The first time you reboot Windows XP after resetting the system clock, Windows XP may try to run the "Desktop Cleanup Wizard". Simply Cancel the "Desktop Cleanup Wizard" at the first dialog.

If you do manage to clean your shortcuts from the desktop and want to recover them, you will find them in a folder called "Unused Desktop Shortcuts". You can recover them as follows:

Double-click to open the "Unused Desktop Shortcuts" folder
Click to expand the "Edit" menu, and click "Select All"
Drag the selected items back to your desktop
Close the "Unused Desktop Shortcuts" folder. You can delete this folder if it is empty.

  Mike43 15:55 07 Sep 2006

Thank you for this very comprehensive answer! What had me fooled was that I had been attempting to charge the battery, but with the computer OFF! I shall now attampt to leave it switched ON and watch for a satisfactory conclusion! Thanks again.

Incidentally, this machine has a slot for inserting a floppy or a CD unit. I have the floppy but never had a CD plug-in. Do you know whether it accepts a specific type or is there a 'generic' CD unit that will fit?

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