Changes to calendar date in BIOS is not reflected in Windows 8

Applies to: Windows 8


Consider the following scenario:
  • You have a computer with Windows 8 installed on it.
  • In your computer's BIOS, you change the calendar date to an earlier date than what is shown in Windows and save the changes.
  • The computer is booted into Windows.

In this scenario, Windows does not reflect the changes made to the calendar date in the BIOS.


This is by design. As real time is unable to go backwards, Windows takes this into consideration if the BIOS reports an earlier date than what is in Windows. In many instances, the BIOS reporting an earlier time and/or date on a notebook computer is due to a failing or dead battery, also making the date and time reported by the BIOS unreliable.


If you need to change the calendar date on your computer, make the change from within Windows instead of the BIOS. This change will be reflected across reboots.

More Information

This design change is new to Windows 8 and did not exist in Windows 7. In addition, it does not affect changes to the calendar date made in the BIOS for dates that are later than what is reported in Windows.