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I've been using archlinux for a while but as the only SO in a hard drive. Today I decided to make a dual boot between windows 7 and archlinux, everything works fine but I have the following problem:

I have set the time in arch for example: 20:00, and when I go to Windows it updates to 01:00.

I've found some other posts like this

and a command hwclock --systohc

but is not working, I guess that I've done everything that I had to do in arch and now I have to fix some problems in Windows but I don't know what to fix

I hope somebody can help me with this because its annoying that I have to fix the time every time I start Archlinux/Windows



The link on the correct answer works but the way it mentions (creating a file and execute it) didn't work for me so I had to do it myself. In case someone want the path in regedit, read this


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up vote 2 down vote accepted

Windows uses local time by default, while Linux uses UTC time. These links may help:

Does Windows 7 support UTC as BIOS time?

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Pretty much everyone should do this on every Windows 7 system they own. About the only exception would be if they have to dual-boot with an OS that cannot support having the hardware clock in UTC. – David Schwartz May 7 '12 at 2:38
According to the links I have to set HARDWARECLOCK to "localtime". What I've done was setting the correct time in archlinux, then run the command sudo hwclock --systohc and then rebooting. Then I start windows (with the wrong time) and run that script and restart but nothing happens – JavierQQ23 May 7 '12 at 2:48
@DavidSchwartz so I have to run the script, then update the time and restart? – JavierQQ23 May 7 '12 at 2:49
Run the script and restart. You should only have to set the clock one more time. – David Schwartz May 7 '12 at 2:59
@DavidSchwartz I ran the script and then set the clock to 20:00 but when I restarted arch showed 15:00. I guess there's something I'm missing – JavierQQ23 May 8 '12 at 2:12

You should Change date and time in the following commands.

date --set "2012-05-06 23:54"


hwclock --set --date="2012-05-06 23:54" 

To probe:

lun 07 may 2012 11:34:00 COT  -0.698178 segundos

I have a dual boot computer with Windows XP and Arch Linux.

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I did that, I set it to "2012-05-07 21:00". Then I restarted and nothing happened – JavierQQ23 May 8 '12 at 2:05

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