Lubuntu stopped booting

[KQuinn]

Hi,
I've been using Virtual Box - currently Version 5.2.6 r120293 (Qt5.6.3) - for a few years now, on a Mac host (10.13.3), and currently with a Lubuntu 17.10 virtual machine. It's always worked fine, but this week my Lubuntu VM won't boot. It starts booting, the blue 'splash screen' appears, then the screen goes black, switches size a couple of times, then sits there with a blinking prompt, and won't progress.
Thanks,
Kev

[socratis]

Most probably a kernel update (due to Spectre/Meltdown), coupled with the fact that you have 3D acceleration enabled. Disable the 3D acceleration and see if that fixes it.

Then, you should try the latest 5.2.x test build, especially with all the Spectre/Meltdown patches coming in from all sides. And after all the updates, you could re-enable the 3D acceleration.

If that doesn't work, we're going to need to see a VM log from a complete VM run:

• Start the VM from cold-boot (not from a paused or saved state) / Observe error / Shutdown the VM (force close it if you have to).
• With the VM completely shut down (not paused or saved), right-click on the VM in the VirtualBox Manager and select "Show Log".
• Save only the first "VBox.log", ZIP it and attach it to your response (see the "Upload attachment" tab below the reply form).

Moving to "Linux Guests" from "OSX Hosts".

[KQuinn]

Hi socratis,
You were spot on, Disabling 3D acceleration sorted it.
Thank you!
Kev.

[socratis]

Great! Now, try the next suggestion, the test builds...