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Ok so here is the problem in short: I run ubuntu 14.04 LTS with two desktop environments: Gnome which i usually use and spectrwm. I removed gnome (followed instructions from somewhere) and left out with spectrwm. I accidentally ran the following command: "sudo apt-get remove unity* ubuntu-desktop" Which caused a disaster (cant access any desktop environment even spectrwm, running on low graphics mode, ...) so how do I revert my last command ? By the way I tried to reinstall ubuntu-desktop and it gave me unmet dependencies errors, I did not try installing any unity package because I do not know which packages got removed because of this command.
Thank you all I really appreciate your help.