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Getting error message at logon "session only lasted less than 10 seconds....", which apparently can be caused by multiple issues. My error is happening during the graphical logon.
I can login to the console by pressing ctrl alt F1. contents of ~/.xsession-errors file indicated that initctl was unable to connect to upstart. The message says that this process is looking for a socket at /com/ubuntu/upstart which is an invalid path on my system.
I created a new user to see if there was an issue with any profile configuration, but the new user graphical logon session also lasted less than 10 seconds for the same reason.
I've updated, upgraded, dist-upgraded, and autoremoved, but no change. I"ve confirmed that cinnamon is fully installed.
I'm running linux mint 18 sarah cinnamon 64-bit. Prior to the 10 second error, all video programs VLC media player and totem player failed to start & reinstall of those packages didn't fix. I rebooted & discovered I had much bigger problem.
I thought that the path initctl was looking for was the wrong one: (/com/ubuntu/upstart) since that file system path doesn't exist.
I used grep & strings to locate another occurrence in lib/sysvinit/telinit. In addition to /com/ubuntu/upstart, I also noted "linux:abstract=/com/ubuntu/upstart. google to http://man7.org/linux/man-pages/man7/unix.7.html said: Linux also supports an abstract namespace which is independent of the filesystem. So I guess this will take more than locating the offending config file & making a change.
So now I'm really in over my head! Anyone have a suggestion on how to fix this?
one last hail mary: removed virtualbox-guest-x11 & rebooted and my system is back. I had previously removed virtualbox package because I noticed it had updates today, but I didn't realize that there was another package included in the offending update.
and it only took 7 hours to fix....... I'm going to post this "question" anyway in case it helps someone else.