Using GRUB to dual boot between elementary OS and Windows 10. After using elementary and rebooting to Windows 10 the time is mysteriously 4 hours off. Just started happening a few months ago. So, every time I reboot to Windows 10 after using elementary I have to reset the time in Windows. Reboot to elementary after using Windows and the time doesn't change. Anyone else seeing this happen to them?
As user Amphyby commented, this is a known situation when you install a distro in dual boot configuration with Windows.
Basically what is happening is that Windows reads the computer time as local time, while elementary reads it as UTC.
Easiest way to solve it is to just run this command in the terminal to set elementary to also read time as local:
timedatectl set-local-rtc 1