My brother had a browser window and Minecraft open when suddenly his Ubuntu 21.10 system froze completely. He did the only thing he was able to: press & hold the power button for a restart. He booted his PC again, but was greeted with a fairly common issue: black screen after login. No mouse cursor, sound or any indication of activity whatsoever.
My first guess was file/package corruption, so I went ahead and tried to reinstall ubuntu-desktop and the display manager through tty. However, networking also did not work for some weird reason (for clarification: it says it is "connected", though the icon is a question mark and there is no network activity).
I went ahead and mounted my installation to a live USB and did everything needed from there. After a restart, though, the black screen and network issues persisted.
For the network issue, I tried editing the /etc/resolv.conf file to include Google's DNS nameservers and the network configurations using nmtui (both wireless and wired), restarting the devices - nothing changed.
For the login issue, I tried renaming the Xorg config files (added the .old extension in case they were the culprits) and starting Ubuntu with the nomodeset option in GRUB, also nothing here.
Thankfully, I did manage to start GNOME Desktop from a tty session using startx /usr/bin/gnome-shell, but that was it. Some software does not work (e.g. Terminal) and there is no networking as I said above.
Is there anything I can do to salvage his installation? He really wants to avoid reinstallation as he has done a lot of customizations on the system.
