Windows & UTC hwclock
Every so often, I have a need to dual-boot Windows with a Unix-y operating system. In the other OS (e.g., FreeBSD), I like to keep the hardware clock set to UTC (the only truly sane setting). Windows does not expose any user-visible setting to keep the hardware clock in UTC but there is a registry key one can set to make Windows behave sanely. Specifically, in:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\TimeZoneInformation
you want to set RealTimeIsUniversal to a dword 1.
That’s it. After this, Windows will no longer adjust the hardware clock during DST changes.
I’ve used this a number of times on Windows 7.
This concludes today’s edition of Note To Self.