virtualbox.org

Everything was working fine until i've updated virtualbox to version 6.1.12; then starting the guest "ubuntu 64bit" after the ubuntu loading page i see a black screen (not blinking underscore or anything). I've already tried to modify the ram size, number of cores, video ram but nothing change.
Creating a new vdi and installing ubuntu virtualbox works and i can log into the ubuntu main page (with the same spec of the other vdi).
Someone can help me with this problem? Or if not possible there is a way to recover the files in the vdi that doesn't start?

I see the guest OS booting, the Guest Additions starting, and nothing seemingly wrong in the log.

The installed Guest Additions are 6.1.4:

00:00:10.393440 VMMDev: Guest Additions information report: Version 6.1.4 r136177 '6.1.4'

There could be an incompatibility, though I wouldn't suppose so, especially as the guest is not using 3D acceleration. You could try to boot into a text terminal in the guest (google for how) and uninstall the Guest Additions, see if that fixes anything.

You could also try downgrading to 6.1.10.

Alternatively, since you have gone on to a different guest, you can add the first guest's drive as a secondary drive to the new guest to get files off.

It may well be the recent-ish (6.1) bug with the screen not refreshing properly on startup. That's been covered dozens of times in these forums: search should turn it up.

scottgus1 wrote:I see the guest OS booting, the Guest Additions starting, and nothing seemingly wrong in the log.

The installed Guest Additions are 6.1.4:

00:00:10.393440 VMMDev: Guest Additions information report: Version 6.1.4 r136177 '6.1.4'

There could be an incompatibility, though I wouldn't suppose so, especially as the guest is not using 3D acceleration. You could try to boot into a text terminal in the guest (google for how) and uninstall the Guest Additions, see if that fixes anything.

You could also try downgrading to 6.1.10.

Alternatively, since you have gone on to a different guest, you can add the first guest's drive as a secondary drive to the new guest to get files off.

I've tried to downgrade at previous versions of virtualbox but nothing change; i think that the problem is not virtualbox but the virtual drive. I can't even boot into the text terminal.
I've recovered the files that i needed luckily so now i can work with the new drive.
Thank you for you help.

Glad you were able to recover your data!