How to change the Date, Time and Timezone in Windows

Why?

Having the correct date, time and timezone on your computer is important. This will prevent and/or fix any issue related but not limited to:

• your web browser stating that the web site certificates are invalid,
• Windows Update not working properly,
• alerts from Windows where it needs to be reactivated again,
• unable to connect to business and/or online game(s) servers. 

If you are experiencing any weird behavior with your application or software, it would be best to make sure that Windows time, date and timezone are accurate. If your computer does have the correct time after being turned off, you should contact the computer manufacturer as the date/time is not being saved in the CMOS/BIOS battery.

How?
For Windows XP, please visit Microsoft Windows XP Help Guide here.
For Windows Vista and Windows 7, please visit Microsoft Windows Help Guide here.
For Windows 8:

• (Note: This guide is also applicable with Windows Vista and Windows 7):
• Go to your Windows desktop (Press Windows Key + D).
• Left click on the time that is displayed in your Windows taskbar.
• Left Click on "Change date and time settings...".
• A dialogue box should appear.
• Click on the "Change date and time...". This will open the Date and Time Settings with a calendar and the current time set in your computer.
• Adjust the date and time as desired.
• Click "OK" when finished.
• To change your time zone, click on the "Change time zone..." button.
• Select the appropriate timezone.
• Click "OK" when finished.
• Make sure that the time is still correct after changing the timezone.
• Click "Apply".
• Click "OK".

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