Daylight Saving Time in Windows 10

What is Daylight Saving Time or DST

Those of you who do not know what is Daylight saving time DST, let me explain in brief.

In most of Europe, local time is moved forward by 1 hour in Spring and moved backward by 1 hour in Autumn. This happens around March or April and ends in October or November. This practice is called Daylight Saving Time. These shifts are different in North and South hemispheres, and may vary from country to country. In the southern hemisphere, the changes are the opposite.

Automatically adjust clock for Daylight Saving Time

Microsoft Windows has established an annual update schedule for Daylight Saving Time (DST) and Time Zone (TZ) releases. From time to time releases DST Cumulative Updates and Updates for Time Zone changes. If you have Windows Update set to ‘automatically install’, there is nothing you need to do, as this will give you a seamless transition to the new Daylight Savings Time and Time Zone settings.

Every country has its own DST implementation policy. Some may not observe DST, while others may change the start dates and end dates for DST every year.

Windows stores time zone information in two locations in the registry.
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\TimeZoneInformation

It is recommended that you use Microsoft Update or download the time zone update from the Microsoft download site instead of manually editing the registry. But if you wish to change the time zone settings manually, you can use the Time Zone Editor or Tzedit.exe tool. This tool lets you create and edit time zone entries for the date and time settings in the Control Panel. You can read more about this at KB914387.

Depending on your Time Zone, if you have checked the Notify me when the clock changes box, you will see this notification in your Windows Clock in the taskbar. By default, the Automatically adjust clock for Daylight Saving Timeoption is checked.


If your time zone does not observe DST, then you will see Daylight Saving Time is not observed in this time zone display.


You can access this Date and Time applet via your Control Panel.

Disable Automatic Daylight Savings Adjustment

If you wish to disable Automatic Daylight Savings Adjustment for some reason, you can uncheck the check-box as shown in the above image. Or you may edit the registry as follows:

Open the Windows Registry Editor and navigate to the following key:


HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\TimeZoneInformation

Here in the right side pane, create a new DWORD Value. Name it DisableAutoDaylightTimeSet and give it a value of 1.