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Thread ID: 88358 2008-03-24 21:56:00 Dual-Booting and System Clock stormdragon (6013) Press F1
Post ID Timestamp Content User
652409 2008-03-24 21:56:00 Hi Guys

For some odd reason after booting into Linux Ubuntu which is installed on a seperate HDD, when I next load Windows the system clock has gone back 13 hours.

Originally Windows shows the correct time, when Linux is loaded it displays the correct time.

Anyone know why its happening and how to fix it?

Thanks
stormdragon (6013)
652410 2008-03-24 22:02:00 It's happening because you told Ubuntu (when you installed it) that the system clock was set to GMT time, not local time. Windows expects it to be local time.

What happens is when you boot Ubuntu, it contacts a time server and updates the system clock. As it's set to use a GMT system clock, the 'correct' time is GMT+0. Then when you boot Windows, it reads the system clock, and assumes that the system clock is set to GMT+13. As Windows is fundamentally useless at using ntp, it never figures out that it's got the wrong time.

Solution: Set Ubuntu to use the system clock as local time, rather than GMT time.
Erayd (23)
652411 2008-03-24 22:16:00 Both Windows and Ubuntu are set to New Zealand time zones. stormdragon (6013)
652412 2008-03-24 22:23:00 Both Windows and Ubuntu are set to New Zealand time zones.I'm not talking about the timezone setting, I'm talking about the system clock setting. The system clock (aka BIOS clock) is used to set the main clock when the computer boots - to do this correctly, the OS needs to know which zone the time is stored in. Erayd (23)
652413 2008-03-24 22:46:00 Where am I supposed to change this in Ubuntu? stormdragon (6013)
652414 2008-03-24 22:56:00 Edit (as root) the file /etc/default/rcS, and change the value UTC=yes to UTC=no.

If you'd prefer to make this change in Windows, set the registry key HKLM\SYSTEM\CurrentControlSet\Control\TimeZoneInfo rmation\RealTimeIsUniversal to 1.

Note that you should only implement ONE of the above methods, not both. You may need to set your clock correctly after doing so.
Erayd (23)
652415 2008-03-25 00:01:00 I'm relatively new to Ubuntu. How do I modify the file as root since you can't login as root? stormdragon (6013)
652416 2008-03-25 00:11:00 Press ALT+F2 to get a run box. In this box type gksudo gedit /etc/default/rcS, then hit enter. It will ask for your password. After you have supplied this, the file will open in the gedit text editor, in root mode. Erayd (23)
652417 2008-03-25 00:20:00 It worked.

Thanks for your help Bletch.
stormdragon (6013)
652418 2008-03-25 07:22:00 Hi Bletch
I just like to make a compliment to your replies!:thumbs:
Are you in the IT industry? Very switched on!!!:D
NT
notechyet (4479)
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