To change the windows 8 / 10 or 8.1 local date and time, please start/open the date and time properties window.
Please press (use) the key combination [Windows Logo] + [R], then just type the command control.exe date/time.
In the date and time properties window click or tap Change date and time [... see Image 1 Arrow-1] and change the Win-8 date and time [... see Image 1 Arrow-2] and/or calendar settings [... see Image 1 Arrow-3].
... To open date-time properties via desktop clicks
Windows-8.1 / 8 Desktop-Clock and click "Change date and time settings..." text and "Change date time ..." button!
(... see Image-2 Arrow-1,2 and 3)
FAQ 76: Updated on: June 24th 2015 14:14