Upgrade from 16.04.x to 18.04.3 broke system - was Upgrade paths from UbuntuMATE 16.04.x and 18.04.x to 19.10

[Bret Busby]

On 14/10/2019, Little Girl <littlergirl at gmail.com> wrote:
> Hey there,
>
> Bret Busby wrote:
>
>>Rebooted.
>>
>>Broken.
>>
>>Upon rebooting, I get the GRUB menu, either wait for it to timeout
>>and boot by default into Ubuntu, or hit <Return> with the default
>>highlighting being for Ubuntu, and I get, first, the terminal level
>>login displayed, then the screen goes black, then I get, in the
>>middle of the screen, the UbuntuMATE logo, with the five dots below
>>it, with them taking turns to change from white to green and back
>>again, below the logo.
>>
>>Then, after a minute or two of that, the screen goes black, and
>>stays black.
>
> This may or may not help, but it worked for us once upon a time when
> we had the dreaded black screen on boot:
>
> https://askubuntu.com/questions/162075/my-computer-boots-to-a-black-screen-what-options-do-i-have-to-fix-it/162076#162076
>
> --
> Little Girl
>
> There is no spoon.
>

But, ..."Just a spoonful of sugar..."

...

The suggested remedy at the URL;

"
If your graphics card is Nvidia, follow these steps:

In the GRUB menu at startup, press e; then,
Use the arrow keys to replace quiet splash with no splash or nomodeset.
Then press the Ctrl+x key combination to boot.
"

worked - thank you for that.

I replaced "quiet splash" with "nomodeset".

Now, ....

as mentioned, the affected computer, is the one where a previous
problem caused me to lose the GUI for my primary user account, leading
me to set up a secondary user account for which the GUI worked.

Now, after the upgrade from 16.04.x to 18.04.3, the secondary user
account GUI appears to work okay, but (I had hoped that the upgrade
would fix the panel problem causing the GUI problem in my primary user
account, but, it did not), now, when I use the switch user facility,
when I try to log in as the primary user, I log in, and, am returned
to the primary user login screen.

Can this be fixed, and, if so, how?


-- 
Bret Busby
Armadale
West Australia
..............

"So once you do know what the question actually is,
 you'll know what the answer means."
- Deep Thought,
 Chapter 28 of Book 1 of
 "The Hitchhiker's Guide to the Galaxy:
 A Trilogy In Four Parts",
 written by Douglas Adams,
 published by Pan Books, 1992

....................................................