Windows 10 Clock in UTC

If you are running Windows and Linux in dual boot, you will soon find out, that the clocks are not matching. Most probable the reason is that Windows by default expects the computer time to be set to local time, while Linux assumes it to be UTC.

I consider the approach of Linux the better one: The BIOS/UEFI system time is there set to a global harmonised standard, UTC. The operating system then translates this to the local time. This means you can install as many operating systems in parallel without interference of them with the system time - just immagine if you have for example, Windows, FreeBSD and two Linux distributions on your computer and every one of them wants to account for daylight saving time .... When setting the system clock to UTC, this problem will never arise.

Setting Windows to use UTC as system time

Registry magic! Create a new registry key named RealTimeIsUniversal.reg with the following contents.

Alternatively you can create a QWORD (or DWORD for 32-bit Windows) with the value "1" in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\TimeZoneInformation\RealTimeIsUniversal

Then reboot Windows and set the time zone to UTC

If unsure, try another reboot to check if the settings persists, but that should do the job.

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