- make sure guest additions are installed (on the guest vm)
- it is a simple matter of the user not being in group “vboxsf” and thus denied usage of vbox filesystem service (fs)
lsb_release -a; # tested on guest Description: Debian GNU/Linux 11 (bullseye) su - root # adding the non-root default user "user" to the group vboxsf usermod -aG vboxsf user # then reboot system reboot lsb_release -a; # tested on host Description: Debian GNU/Linux 10 (buster) # if there are still access errors try on the host chown -R ugo+r /path/to/shared/folder