How can I fix the incorrect Windows time after dual-booting Linux Mint?

This happens because Windows and Linux usually interpret the computer’s hardware clock differently. Windows generally stores it as local time, while Linux typically treats it as UTC. You can either configure Linux to use local time or configure Windows to use UTC so both systems agree.

First check the time zone settings in both operating systems and in the BIOS/UEFI. Set the firmware clock correctly, then let each operating system synchronize its time. If the clock is still offset by exactly a few hours, it is almost certainly the UTC-versus-local-time configuration rather than a time-zone problem.

On Linux Mint, you can make Linux use the hardware clock as local time by running `sudo timedatectl set-local-rtc 1 --adjust-system-clock` in a terminal. After that, correct the clock once in Windows if necessary. Another option is to leave Linux using UTC and change Windows to use UTC instead.