Create the mount point or storage directory.
# mkdir /var/vmail
Create a new group called "vmail" and assign a group id of 5000.
# groupadd -g 5000 vmail
Create a new user called "vmail" and assign a user id of 5000.
# useradd -u 5000 -d /var/vmail -s /usr/sbin/nologin -g vmail vmail
Change ownership and permissions on the vmail directory.
# chown vmail:vmail /var/vmail -Rf # chmod 700 /var/vmail
