I had a weird issue that every time I start my PC I had to manually sync my clock as if it was not updating time automatically. I tried to change all possible system setting but issue was same.
But, next thing I noticed that clock was always right on booting into Ubuntu OS on same machine. So after little research I found out that Ubuntu sets hardware clock to UTC mode whereas Windows set it to local time and that conflict was causing clock on windows go out of whack.
So there were two ways I could fix the clock right, one is to change windows setting to make it refer hardware clock as UTC which Ubuntu sets but it required messing with windows registry and as you know it is not advisable to mess with registry unless you really know what you are doing! so I preferred second way which is to change setting on Ubuntu to make it set RTC in local time zone and it was relatively easy to follow.
So if you are facing same issue please try to run following commands and restart you pc and it will put end to this annoying issue.
First of all check if RTC in local TZ is set to no by running following command
Then run following command to set RTC in local TZ to yes.
timedatectl set-local-rtc 1 –adjust-system-clock
Verify that it set RTC in local time zone and restart pc. You may need to set clock final time after you boot into Windows.
Voila! you got rid of one annoying issue. By the way this might also help in other windows update issues you are facing because of clock mismatch.