Hey Geoff,
I'm guessing this is perhaps Ubuntu 18.04 or higher?  And perhaps you 
started to get this crash shortly after updating your kernel and/or 
graphics drivers/card?
Basically that last thing in the boot sequence (the 'GNOME Display 
Manager', or GDM) is the thing that starts up X.org (which is the 
process that runs the graphical environment)... and since you can still 
see text, that must not be working.
I'd advice rebooting into recovery mode and from the recovery menu there 
might be an option for something like 'failsafeX' or something like 
that... so that you can get back into the graphical environment with a 
safe low-end graphics mode to fix things.
Probably a DKMS module (e.g. if you use NVIDIA or AMD graphics) didn't 
get re-installed from your last kernel upgrade.
Let us know if how you get on, but that should point you in the right 
direction.
Also from your postcode, you'll probably find WolvesLUG more local if 
you need to reach out to someone who lives near by (we're happy to have 
you here too :P)
p.s. With you mentioning pubkey errors... that's likely (at a guess) 
something you're seeing with APT (or something that calls it, like 
whichever program you install software using) and probably just means 
you need to update your repo's... but it's probably not related to this 
issue.
Steven Maddox
Lantizia
On 01/10/2025 10:48, Geoff Whiles via StaffsLUG General wrote:
 Hello,
 I am a user of Ubuntu and have been since the release of 12.04. I have 
 little understanding of the workings of Linux, though I have several 
 heavyweight tutorials and I'm not afraid to use the Terminal. I use 
 Ubuntu as a means to an end, in day to day home computing. Forgive the 
 terminology, but I am neither a geek or programmer.
 The system has completely crashed. Attached are several pics. I won't 
 witter further, so as not to complicate my dilemma. I should add that 
 I also get many pubkey errors, and also whilst booting, the whole 
 system hangs and I have to hard break to shut down.
 I hope that this message lands with someone who can dig me out of this 
 almighty hole or maybe refer me to someone who might be able to help. 
 And of course, I am happy to pay for any work undertaken.
 Kind regards
 Geoff Whiles
 WS11 0GU
 07711014256
 Notes from my machine:
 Select Boot Device
 P1: ST3250820AS
 P0: HFS128G3AMNB-2200A
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