Adding group `postfix' (GID 115) ...
Done.
Adding system user `postfix' (UID 107) ...
Adding new user `postfix' (UID 107) with group `postfix' ...
Not creating home directory `/var/spool/postfix'.
Creating /etc/postfix/dynamicmaps.cf
Adding tcp map entry to /etc/postfix/dynamicmaps.cf
Adding sqlite map entry to /etc/postfix/dynamicmaps.cf
Adding group `postdrop' (GID 116) ...
Done.
setting myhostname: ubnt-server-14.04
setting alias maps
setting alias database
changing /etc/mailname to ubnt-server-14.04
setting myorigin
setting destinations: ubnt-server-14.04, localhost.04, , localhost
setting relayhost:
setting mynetworks: 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
setting mailbox_size_limit: 0
setting recipient_delimiter: +
setting inet_interfaces: all
setting inet_protocols: all
/etc/aliases does not exist, creating it.
WARNING: /etc/aliases exists, but does not have a root alias.

Postfix is now set up with a default configuration.  If you need to make
changes, edit
/etc/postfix/main.cf (and others) as needed.  To view Postfix configuration
values, see postconf(1).

After modifying main.cf, be sure to run '/etc/init.d/postfix reload'.

Running newaliases
newaliases: warning: valid_hostname: numeric hostname: 04
newaliases: fatal: file /etc/postfix/main.cf: parameter mydomain: bad parameter value: 04
dpkg: error processing package postfix (--configure):
 subprocess installed post-installation script returned error exit status 75
Errors were encountered while processing:
 postfix
E: Sub-process /usr/bin/dpkg returned an error code (1)