Hello, I tried your tutorial but it doesn't work on my side. I have wordpress folder at this location:

/var/www/html/wordpress

Therefore, my root folder for my websites should be /var/www/html. Here is the I run in order to do all the steps:

userdel sftp;

useradd sftp --home-dir /var/www/html \
                 --gid www-data \
                 --shell /usr/sbin/nologin \
                 --password 'test'
                 
for dir in /var /var/www /var/www/html ; do
    chown root:root $dir
    chmod 0755 $dir
done

chown -R www-data:www-data /var/www/html/wordpress;

find /var/www/html/wordpress -type d -exec chmod 2775 {} \;
find /var/www/html/wordpress -type f -exec chmod 0664 {} \;

rm /etc/ssh/sshd_config.d/sftp.conf
cat >> /etc/ssh/sshd_config.d/sftp.conf <<EOF
# SSH config for SFTP only user
Match User sftp
    ForceCommand internal-sftp -u 002
    ChrootDirectory /var/www/html
    PasswordAuthentication yes
    X11Forwarding no
    AllowTcpForwarding no
    AllowAgentForwarding no
    PermitTunnel no
EOF

  And after:

systemctl restart ssh;

sftp sftp@localhost

When I try with password = test,   I have permission denied error. I have uncommented line "Subsystem   sftp    internal-sftp" in /etc/ssh/sshd_config.   Do you know why I got this error? Thank you in advance, Arno.