If Set Time Automatically is on, turn it off. This setting merely enables users to display their preferred time zone while being synchronized with domain controllers in different time zones. Alternatively press “Win + I” shortcut keys to open Windows Settings app. Scroll down until you get to Screen timeout settings and click it. Here is how to change the taskbar time to 24-hour format in Windows 10. Then, click the gear icon to open the Settings. System – Windows settings In the display settings, under the “Scaling” heading, click on the dropdown.