unity - Ubuntu 14.10 no desktop after kernel update to 3.18.1

Using 14.10 with an ATI Radeon 5450 graphic card.

Everything was working fine after installing ubuntu 14.10. Then 1 or 2 weeks ago after a normal update, some applications started crashing (thunderbird, firefox, eclipse and sometimes also chrome).
To solve the crashes, I decided to update the kernel to 3.18.1 and see if it improves it.

Now, I no longer see the desktop (no launcher bar, no unity bar etc). The only thing I get is the wallpaper and the mouse.

Ctr+Alt+T doesn't work nor right click on the desktop.

I know that there are many similar problems on the net but none of the solutions worked for me (I'm trying for many hours now).

Solutions I've tried with no success:

Using Ctr+Alt+F1

1. uninstall and reinstall fglrx




2. export DISPLAY=:0
ccsm

   
   
   

   Enabled the openGL and unity plugin.

   
   
   
   

   Important: The window of the ccsm did not have any title bar and could not be dragged !!




3. Installed gnome, logged into ubuntu using gnome and got the same empty desktop.




4. Tried re-installing compiz, ccsm, unity desktop, unity.




5. sudo dconf reset -f /org/compiz/

   
   
   

   than making sure using export DISPLAY=:0 and ccms that the openGL and unity are still checked.

When running sudo unity I'm getting an error:

...
...
compiz (core) - Error: Plugin 'opengl' not loaded

6.

Installed the open graphic drivers

Removed fglrx

dconf reset -f /org/compiz/

and

setsid unity

Restarted lightdm and got everything back. I was happy and everything worked fine for two hours until ubuntu crashed and does not start anymore. It now shows a black screen with only a cursor which probably means that also the open drivers are not good.

Any ideas?

Thanks a lot (:

UPDATE

The crashing was due to a hardware problem. The memory cards where somehow not sitting correctly in their slots. I could not even install from the Live CD because it was crashing with different kernel panic errors every time.

After testing the memory cards one by one and fixing them back correctly, everything worked and I installed a fresh Ubuntu 14.10 (I had to do it because of all the half crashed installation tries). Everything works fine now.

So the solution to the drivers problem was actually solved after installing the open drivers as suggested by Νίκος Φυτίλης

I'm going to add an answer and signed it as the correct answer

Hope it helps someone (:

I'm answering my own question.

First, I installed the open graphic drivers as suggested by Νίκος Φυτίλης

HOW? WHAT IS THE ACTUAL COMMAND?

Afterward, I removed fglrx, but I still didn't get the desktop bars (unity and the top bars).

sudo apt-get remove fglrx                                                       
sudo apt-get install fglrx

I wanted to reset compiz but got some errors that the display is not found because I was using the only accessible terminal Ctr+Alt+F1

So after using export DISPLAY=:0 before reseting compiz, everything came back (:.

export DISPLAY=:0
sudo dconf reset -f /org/compiz/  <<<<<<<<<<<<< THIS COMMAND DOES NOT WORK FOR ME?
sudo setsid unity

Restarting lightdm...

sudo service lightdm restart

... brought everything back (: