I've been trying to install Guest Additions for Raspbian Desktop on VirtualBox hosted on Linux. The script won't run even under root. How is it possible?
8.
of the preferred answer here. Not much of an explanation, yet it certainly works.
# sh /media/cdrom0/VBoxLinuxAdditions.run
In my case this worked for me.
$ sudo apt update
$ sudo apt install build-essential module-assistant dkms
$ sudo m-a prepare
then select the menu devices/insert guest...
CD is mounted and select ok
$ sudo sh /media/cdrom/VBoxLinuxAdditions.run
$ sudo reboot
proudly borrowed from, https://www.neontribe.co.uk/debian-virtualbox-guest-additions/
I don't know why root wouldn't work for me sudo -i was enough