VAIO Computer System Reference Manual
If the error message "Error: Check date and time settings." appears
during the reboot sequence, press F2 during the reboot process to
access the BIOS Setup Utility. If no error message displays, the
computer's BIOS settings were retained during the battery
replacement and you can skip the remaining steps.
Refer to the list you made in step 3 and restore any non-default BIOS
Select Exit Saving Changes from the main menu using the right arrow
Press Enter, type Y when prompted to discard changes, then press
Enter to exit the BIOS Setup Utility.
The computer's BIOS settings are now restored.
"CMOS Setup Options"
on page 51).