"Can't install gnome-desktop-environment, gnome-keyring-manager not installable"When trying to install the gnome desktop with either the terminal or Synaptic Package Manager.
Some searching led me to advice to type both of these commands in the terminal (don't type the $, and you may have to type "sudo" before the apt part...)
$ apt-cache show gnome|grep Depends|cut -f2- -d:|tr ',' '\n'|cut -f2 -d' '|grep -v gnome-desktop-environment|xargs sudo apt-get install -y
$ apt-cache show gnome-desktop-
environment| grep Depends|cut -f2- -d:|tr ',' '\n'|cut -f2 -d' '|grep -v gnome-keyring- manager| xargs sudo apt-get install -y
Found this in a launchpad support forum (bugtracker). https://bugs.launchpad.net/ubuntu/+source/meta-gnome2/+bug/216756
Be warned this may take the better part of an hour to install (the rest of your system should be usable while it installs.)
I ran both of these commands, and yes, it worked. Next time I rebooted, I had the option of a Gnome session, and it seems to be running smoothly so far.
Other links I found had some interesting info, if you want further reading:
Lock issue I encountered in the meantime (oopsie.) Thought it was a bug until I realized I should listen to actual directions (ARE YOU RUNNING AS ROOT???... i.e. use sudo)
Launchpad bug that actually indicates it's a duplicate of another bug.