Windows 8 (and most (all?) other MS operating systems) keep the
hardware clock running on local time (it has been a peeve of many in the computing industry for a long time - especially for those who dual-boot into
Linux or Unix). There are a couple of things you can try:
1. Restart the computer and enter the computer setup/BIOS/CMOS routine. This is usually a function key press while restarting but different vendors use different keys or key combinations. You'll have to watch your
screen for "press [key] to enter setup".
Check the date/time (and possibly timezone depending on vendor) in the BIOS for the CMOS clock and set these to the correct local time.
Reboot into Windows and see if that helped. Windows should then update the BIOS to be accurate to the second using the
internet time, so as long as you get it reasonably close in BIOS that's a good start.
2. There is an optional setting in Windows called "RealTimeIsUniversal" that allows the CMOS clock to be kept in UTC. This is not a perfect tool and in not fully supported by Microsoft, if it has been set then it could be causing problems. To check use the registry editor (Start - Run - Regedit) and then search the registry (Ctrl-F) for "RealTimeIsUniversal" or just look for it here:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Contro l\TimeZoneInformation\RealTimeIsUniversal
If you don't see RealTimeIsUniversal (RTU) then it is not being used and is not a problem. But, if RTU = 00000001 then is being used. You can delete the key or change it to zero and then reboot and see if that helps (all the usual caveats about editing the registry, care, caution, etc.).
Those are the two most common issues I've found in Windows machines used around the world, but if neither of them helps then I might dredge my brain for a few more.