when I go to change the date and time it doesn't work, and I try to unlock but it just won't unlock, if there is any way to make it work please help. I know it isn't very descriptive but I really would like some answers. thank you

From man date

-s, --set=STRING
          set time described by STRING

To change date, use the command in terminal,

sudo date --set=STRING

For example, to change date to 25 Sep 2013 15:00, the command would be,

sudo date --set "25 Sep 2013 15:00:00"
  • Does it also work if system is rebooted or it has to be apply every time after reboot? – YumYumYum Apr 30 '14 at 3:20
  • 1
    Yes, it works after system reboot; you wouldn't have to apply it every time. – kern May 1 '14 at 5:35
  • After reboot system is automatically picking current date. – Naveen Mar 31 '16 at 5:56
  • If the date appears to be something way wrong after a reboot or power cycle, it usually means the battery on the motherboard is bad. – Andi Jay May 5 '17 at 15:36
  • 2
    This appears to no longer work. Using Ubuntu 16.04 – Teekin May 30 '17 at 15:06

Try this:

sudo dpkg-reconfigure tzdata

This both lets you configure your timezone (you may just pick the same), and automagically synchronizes your time.

If there's no tzdata package, install it:

sudo apt-get update
sudo apt-get install tzdata
  • This solve my Ubuntu server timezone setting, thank you. – Manee Osman Dec 20 '16 at 6:21

In 12.04 I don't have to Unlock anything. Just click on the clock on the top bar, and choose Time & Date Settings, once the Time & Date window opens, choose Manually, so you can change the time and date manually; otherwise choose your time zone from the map, and choose Automatic.

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  • 4
    I am not able to change my system's time this way. I can change the time from the settings but it is not reflecting on my top bar. – roopunk Jun 26 '14 at 10:50
  • 1
    It takes a while (+30 secs), but the top bar does update after sometime. (Ubuntu 14.04) – shxfee Oct 25 '14 at 19:37
  • You'll have to change the focus of the Date spinner control to have the date changed immediately. Very odd :) (Ubuntu 14.10) – Aram Paronikyan Mar 2 '15 at 14:03
  • 1
    None of these solutions work for me, am on 14.04 as well. – Tass May 27 '15 at 17:25
  • sometimes to reflect the settings changes you need to kill unity panel service and restart it. Click clock on the top bar, and choose Time & Date Settings once the Time & Date window opens choose Manually so you can change the time and date manually; otherwise choose your time zone from the map, and choose Automatically. Now to reflect changes instantly open terminal and type killall unity-panel-service – Gaurav Shukla Aug 20 '15 at 22:58

See this blog post for setting the date with a machine-friendly format string:

sudo date 120622432007.55

for December 6, 2007, 22:43:55,

and see this answer for setting the date with a human-friendly string:

sudo date --set "15 MAY 2011 1:40 PM"

I had similar issue on my install and the above command gave this error:

date: the argument '19 Sep 2014 20:11:00' lacks a leading '+';
when using an option to specify date(s), any non-option
argument must be a format string beginning with '+'
Try 'date --help'

Help shows -

Usage: date [option]...  [+FORMAT] - (etc)

Added the required plus as indicated to render +19 Sep 2014 20:11:00 which worked.

  • This is for displaying the date, not setting it. – Adam Katz Oct 24 at 0:43

protected by souravc Apr 28 '17 at 6:45

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