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I have been having a problem with Ubuntu ever since I installed it. I have no clue why it is doing it, but I will try to provide as much detail as possible. First, I want to say that I am duel-booting with windows 7. Secondly, this is not the only time this has happened (I think it might be because of Ubuntu 12.10 because it never "not booted" when I used Ubuntu 12.04), but instead, this was with another PC. This is very strange to me because I have two laptops and one desktop (I’m using the desktop which has the boot problems), and this is strange because I INSTALLED Ubuntu on a fairly old laptop and I duel booted with the good one...the good one booted like, 1/4 times while the old laptop booted 100% of the times. Now, I don’t know if this is because I'm duel booting or not but it is still, very unclear to me.

Now, onto what happens on screen. I’m sure that some of you out there would know what the duel booting screen looks like, it has that purple background with the white text (including the booting options). Now when I select the Ubuntu booting option, it stays on the same screen for a couple of seconds, then, it cuts to a purple screen for approx...10 seconds. after those couple of seconds, a semi-error screen will pop up (this is nothing but a cluster of black lines and other colors of the rainbow(this would last for about 1.3 seconds)). Then (this is path 1), a black screen this time with the text:



Note that the '_' will continue to flash, might I add that the mouse is highly visible on the screen and is movable (what I think this means is that I’m on the desktop but nothing is visible. And now path 2. now, path 2 consists of another black screen but no text is visible, only the mouse is.

OK, now onto what happens when it does work. Everything is normal (except for everything being slow, but I think its best that we work out this issue first), now what do I mean by normal? Imagine a video showing you "what to do after installing Ubuntu", it looks just like that. no UI screwing up or even problems updating, just everything being...good.

BTW if anyone wants to know the specs for this PC, there right here. Ill also be listing what monitor I'm currently using:

Note, if anyone needs a video of what it looks like when loading up Ubuntu, I would be happy to do that (I'll include a youtube video), but ill only do that if its like "the last hope for man-kind".

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up vote 2 down vote accepted

For the blinking _, switch to tty1. (CTRL+ALT+F1)

At there, type:


If that throws up errors, please put them in your question. Then try:

sudo service lightdm restart

If that doesn't work, try this:

DISPLAY=:0 unity --replace

Please post any errors.

This is to restart the GUI.

Edit: Looks like you need to re-configure LightDM and reinstall Unity.

You will need to use startx and open a terminal.

To re-configure LightDM, do in a terminal:

sudo dpkg-reconfigure lightdm

To reinstall Unity, do:

sudo apt-get update
sudo apt-get install --reinstall ubuntu-desktop
sudo apt-get install unity

then do a sudo apt-get update just to make sure.

Hope this helps!!!

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Hello, so i did everything that you said and it booted to the desktop just fine(also, every time i use the command, sudo service lightdm restart, it boots fine every time). here are the results: fatal server error: no screens found (EE) please consult the The foundation support at for help (EE) please also cheak the log file at "/var/log/Xorg.1.log" for additional information (EE) server terminated with error (1). closing log file. xinit: giving up xinit: unable to connect to X server: connection refused xinit: server error – Watergoshi Apr 11 '13 at 22:36
What command was this output from? – horIzoN Apr 12 '13 at 8:35
it was from: sudo service lightdm restart – Watergoshi Apr 12 '13 at 11:47
@Watergoshi - See edit. – horIzoN Apr 12 '13 at 15:59
Hello, I’m sorry to say but, the reinstall unity and lightdm did not work. however, I’m happy to announce that I reinstalled Ubuntu by downloading a 64-bit version of it then replacing it with the 32-bit version that I had previously (which might have cause the problem). And now "does it work?" YES, I have booted it up like 15 times and I haven't seen any problems with the start up. even if they do appear again though, ill just use the "Sudo service lightdm restart" command that you showed me before. I’m just sending this comment to show that its working again. (PS: my win7 was 64-bit too) – Watergoshi Apr 13 '13 at 4:31

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