Posted 2015-04-23 to Ben Burwell's blog
When I upgraded to Ubuntu 15.04, I was unable to log in. The machine started normally and I was presented with the login window. But when I entered my password, the screen went black for a few moments and then the login screen came back.
Since I’m using an NVIDIA GeForce GTX 750, which Ubuntu’s Nouveau drivers don’t support, I previously needed to install the NVIDIA graphics drivers.
By entering Ctrl + Alt + F3, I was able to drop
to a shell. When I checked
/var/log/Xorg.0.log, I found a message stating that
the NVIDIA driver had failed to load the GLX module, despite earlier messages
that it had been loaded. The message also recommended reinstalling the NVIDIA
In the same shell, I ran:
wget http://us.download.nvidia.com/XFree86/Linux-x86_64/349.16/NVIDIA-Linux-x86_64-349.16.run chmod u+x NVIDIA-Linux-x86_64-349.16.run sudo service lightdm stop sudo ./NVIDIA-Linux-x86_64-349.16.run
After that, restarting my computer cleared up the issue.