password restrictions are different in the GUI and on the command line.

Chris Green cl at
Sun Jul 17 15:40:19 UTC 2016

On Sun, Jul 17, 2016 at 05:14:09PM +0200, Ralf Mardorf wrote:
> On Sun, 17 Jul 2016 16:30:38 +0200, s.achterop at wrote:
> >This because lightdm seems to enforce the stricter rules that are used
> >when setting a password using the GUI.
> Hi,
> there might be a GUI available to add a user, resp. to chose a
> password and this GUI might recommend or even enforce to chose a more
> secure password, but I doubt that lightdm doesn't work with a simple
> password such as "cat1234", "dog5678" or "12345678", when such a less
> secure password was chosen by command line.
> How did you notice that lightdm doesn't work with a simple
> password, chosen by command line? Did you get a message? Is there an
> entry in the log file saying this?
> You did not enter your simple password, while by accident caps lock was
> active or something like this?
The other thing that can cause confusion is that (sometimes) lightdm
doesn't have the same country setting for the keyboard as the rest of
the system.  On mine it resolutely stayed at US English whereas I had
the system installed for UK English.  

This can mean that any non alphabetic characters are entered wrongly
in lightdm.  

You can check by trying to login for a different user and typing your
password as the user name, you may well find the characters are not
those you expected!

Chris Green

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