I am running Linux Mint18.1 and Windows 10 in dual-boot installations on a number of PC's, all of them Dell Optiplex desktops and Dell Latitude laptops. I am geting the same problem on all of them. Although time is on auto (network-provided time) and time zones on all systems to +2 (Athens) whenever I boot Windows after Linux the clock on Windows will be two hours behind. The time in Bios changes as well. The time does not change when I boot consecutive instances of Windows, only when Linux comes into play. I use Linux for 90% of my work, Windows is dedicated only to Photoshop, Lightroom and Media Monkey. Still I cannot do without Windows otherwise I would uninstall them. Any suggestions as to how I can correct the problem?

You have a mis-match in timezone handling - Windows has always used localtime, and *nix UTC. I believe with Win10 you can coerce it to change, but easier to run Linux in Athens localtime. Mint should have a howto somewhere, but this might get you started.

To elaborate a bit the mismatch is due to what linux uses as the timezone for the hardware clock. There is no BIOS setting for timezone. As stated Windows defaults to local time and linux UTC and this causes the time to be off when you switch to the other operating system.

By changing Mint to use localtime for the hardware clock should resolve your issues. Using systemd the way to change the configuration setting is:

sudo timedatectl set-local-rtc 1


The actual configuration file is /etc/adjtime.

Are Mint using systemd these days ?.

I thought that 18 switched to systemd but I could be wrong...

change your Linux systems rc.conf file to "localtime"
to set time date in Linux and set the hwclock

Yes. Starting with Linux Mint 18, Mint is based on Ubuntu 16.04 which uses systemd.

Thanks; hope they did a better job than Debian appeared to have done - seen plenty of issues reported here. Time to go upgrade one of my old Mint systems.

Thank you all and Happy New Year. The problem has been solved.