You have a problem with the log file path and share name, here is how to fix that, first we fix the log file path here, open this file /etc/samba/smb.conf
then search for a line that start with log file
and change it so that it look like that log file = /var/log/samba/log.%m
then check that the path specified by your system for the log file exist and have the proper permission
sudo mkdir -p /var/log/samba
sudo chown root:adm /var/log/samba
sudo chmod 750 /var/log/samba
for the share name it should not contain any of those character % < > * ? | / + = ; : , "
and there is /
in /media/ubuntu/e42804db2804af1c/aj
just use something like aj
or test
if is temporary, then restart properly and it should work. sudo systemctl restart smbd nmbd
edit: following your comment the problem might be related to the way the GUI is creating the share name, here what you can do, first check the permission for example for /media/ubuntu/e42804db2804af1c/aj
we do ( replace your_username with yours )
sudo chown -R your_username:your_username /media/ubuntu/e42804db2804af1c/aj
sudo chmod -R 755 /media/ubuntu/e42804db2804af1c/aj
then in /etc/samba/smb.conf
add those ( replace your_username and path with yours )
[aj]
path = /media/ubuntu/e42804db2804af1c/aj
browseable = yes
read only = no
guest ok = yes
create mask = 0644
directory mask = 0755
force user = your_username
save and restart sudo systemctl restart smbd nmbd