[xubuntu] xfce4 problem. Packages disappeared?

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http://ubuntuforums.org – Hello! First, thanks for reading this. I installed Ubuntu several months ago and have been learing how to use it and etc. I liked a lot, but it went a bit slow in my computer, so I decided to install xcfe, which in some forums people said it was faster. After reading a lot, I installed it from the terminal with this command: Code: sudo apt-get install xubuntu-desktop I did this like 3 weeks ago. I did not delete gnome since I read that it was better to try it first and that also it may be dangerous. Well, everything was fine until today. When I turned on the computer and logged into (Hardware)