How to correct your Windows system clock
To correct your Windows system clock:
Windows XP
- Double-click your clock in the lower-right tool tray, or from the Windows Start menu choose Settings > Control Panel > Date/Time.
- In the Date and Time Properties dialog box, set the correct date and/or time (note AM or PM) and time zone, then click OK.
Windows 7 and Vista
- Click on the clock at the right/bottom of your taskbar
- Click the link for Change date and time settings…
- Then click on the Change date and time... and correct the date and/or time.