The way was long and painfull until here, but... You will see
The story: I wanted to upgrade my Laptop from Ubuntu 14.04 to 14.10. After applying the update I remembered the situation I was in: I had a black login screen with just a cursor. Last time I just did reinstall ubuntu, because it was the LTS version and I did not feel bad about the upcoming work (since it was an LTS version)
After I got rid of that black screen - I'm still not sure how - I had the lightdm login screen which I exchanged with the 'regular' one. After dealing with ubuntu won't let me login and resending me straight back to the login screen I had the problem that Unity (launcher and top bar) wasn't starting.
The main problem at that time was that
did give me the compiz manager where I could select the unity-api box (which was unticked) so that the unity launcher did show up again, but whenever I restarted there was no unity launcher, no top bar no nothing (except my main desktop background).
Somehow - again not shure how - I did manage to get back the launcher and the top bar. Since I had some nasty problems with the Xserver on my system in the past I changed the GPU driver to fglrx-updates (which worked perfectly fine in 14.04 !). The download was OK and unlike the few times before when I tried to select it and it reset the ticked box to the Xserver in the ubuntu options. Now I have - at least I guess that I have - fglrx-updates installed and...
...I'm back to the black screen with the blinking cursor. Hurray for nothing :-(
So I'm not sure what I should do now. Does anybody know what has happened there? Is there a faster way of getting back to my system without spending about 6 hours of my time like I did last time?
To be brutally honest: Since ubuntu is one OS on my dual boot machine I thought about removing it completely from my system. Even I somewhat like to work with it I just don't have the time to spend hours on just a black screen and - this is the 'sad' thing for me in that story - I did not ever have such problems with Windows before.
Update: This is how I got back to a working (?) system:
- Press Ctrl+Alt+F1
- log in and run
sudo -sto become a root (saves retiping passwords)
sudo apt-get remove --purge fglrx*
sudo apt-get autoremove
sudo apt-get install --reinstall ubuntu-desktop
sudo apt-get install --reinstall unity
sudo apt-get install compizconfig-settings-manager
rebootrebbots your system (now I can see at least the login screen)
- if Ubuntu does not log you in but jumps back to the login page help can be found here
- Again Ctrl+Alt+F1
- Make shure the Unity Plugin Box is ticked
Now I have at least a working system where I have a GUI, but I can't play games any longer (like eg. LIMBO) which is not what I want to have - I don't need an 'just browsing the web' OS! Even I updated my system, I do not want to select fglrx-updates as my display driver again, because I'm pretty shure that I will get a black screen again.
If you have any comments, found a fail in the code above or want to tell me how I get back my working system I would love to hear from you! :D
Things that I have done before on my system while trying to head to a GUI which may help you:
sudo apt-get install --reinstall linux-headers-generic
sudo apt-get install --reinstall lightdm
sudo apt-get install lightdm-gtk-greeter(installed the lightdm login screen)
sudo apt-get remove --purge lightdm-gtk-greeter(removed it and - I guess - swichted back to the regular one)