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I was just goofing around in a vm to test what would happen if I purgen unity:

sudo apt-get remove --purge unity*

I found that I get an startup error, but when I proceed, I got this awesome login screen: all sexy It has an sexy effect and is just the gnome style my whole pc has got.

So can any one please tell me how I change the default login screen program without having to bother clicking "fix this error" on every boot?

Thanks in advance.


I have been able to change it(my own answer), but now I see the old purple background for a second when I logged in, and that background is only used in the old greeter screen. How do I change it(or where are those backgrounds located)?

share|improve this question
What is the error? – Frantique Nov 13 '12 at 10:51
uhhh, lemme crash my vm again, 2 sec. But it is in no way a addition to my question. – Dr_Bunsen Nov 13 '12 at 10:53
up vote 4 down vote accepted
sudo dpkg-reconfigure lightdm

I selected gdm, and now I have the login screen I desire.(This replaces lightdm with gdm)

Thanks for the other suggestions, I found that this was the only one to work, since gnome has it's own desktop manager(gdm).

share|improve this answer

Boot in recovery mode, select root shell and issue: dpkg-reconfigure -phigh xserver-xorg. The error is related to misconfigured xorg. Have you installed the virtualbox extension pack? If not, do it!

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thanks, but I dont mind the error, but the login screen it revealed, how do I install that? thats my question. – Dr_Bunsen Nov 13 '12 at 13:01
Get rid of error, and you will have the login screen. – Frantique Nov 13 '12 at 13:04
well surely there would be a nicer way to change the logon screen, I mean, we can edit anything here, why should I have to break 50% of my system to change a silly logon screen? – Dr_Bunsen Nov 13 '12 at 13:11

If you are using lightdm as display manager, you can change the greeter in /etc/lightdm/lightdm.conf.

For example to use lightdm-gtk-greeter (=xfce greater):


# Other options:

# to change unity to xfce session on default:
# or to xubuntu:

# hide users

# disable guest login

As you can see there are more customization options to hide users or to select the default session for example. I don't know the name of the login screen on your picture so I used the one I use on my machine but I guess you can find it out on your virtual machine and use it on your main if that is what you want to do.

share|improve this answer
Thanks, I will try this. – Dr_Bunsen Nov 13 '12 at 13:21

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