I have been having problems with my Ubuntu 12.04 LTS installation (dual boot with Windows 7). Whenever I install some update OR if the machine is stuck & I try to do a hard reboot, the OS never boots back and either shows the message :
could not write bytes : broken pipe
OR shows a black screen with a cursor on top left :
_
I don't think I have done really wrong with my Ubuntu ( a hard reboot shouldn't break a OS .. everyone does that); just now it happened after I just installed a new copy and rebooted after some steps (see edit).
I want to ask what are the causes of these errors as I want to find a permanent fix to this problem. Can someone suggest how I could diagnose the problem with my machine ?
Edit
One thing I would like to add to my question, since I am getting some responses and I need to give accurate description. I forgot to mention, that I tried to compile Android on my machine. That requires the following step (I didn't know it would effect the machine because of my lack of experience - but now I think I need to mention it) :
sudo apt-get install git-core gnupg flex bison gperf build-essential \
zip curl zlib1g-dev libc6-dev lib32ncurses5-dev ia32-libs \
x11proto-core-dev libx11-dev lib32readline5-dev lib32z-dev \
libgl1-mesa-dev g++-multilib mingw32 tofrodos python-markdown \
libxml2-utils xsltproc
See here.
When I try to this, it removes a lot of packages related to xserver/xorg, because one these has a dependency; when I try to apt-get that dependency, it removes many packages. Could this be causing the problem ? Could someone please try running this ? (I don't have experience with these packages)