Err_cannot_create_subdir, help please

Ubuntu VM, smb share mounted to /media/urbackup

I’m getting the following error:
The directory where UrBackup will save backups is inaccessible. Please fix that by modifying this folder in ‘Settings’ or by giving UrBackup rights to access this directory. (err_cannot_create_subdir). Permission denied (code: 13)

Other than that i have nothing else to go on. Literally nothing in the logs, completely empty.

I’ve played with the permissions and done several things suggested here and elsewhere but i’m not getting any further.

Edit: tried creating a share just for urbackup with a dedicated user but no cigar
Edit2: magically worked when using an nfs share instead

Assign 777 permission for “urbackup” user for /media/urbackup.
urbackup is the default user.

login as root
chown -R urbackup /media/urbackup
make sure urbackup user has 777 permission set on /media/urbackup