phpmyadmin error during installation "Empty value for 'port' specified."

My machine configuration - Ubuntu 16.04 - MySql 5.7.13 - PHP 7.0.8 - Apache 2.4.18

Edit the file /etc/dbconfig-common/phpmyadmin.conf, changing

dbc_dbport='' to dbc_dbport='0'

After editing the file and saving it, if you are still on the dbconfig-common wizard select retry; if not run sudo dpkg-reconfigure phpmyadmin (choose Yes when asked you if you want to Reinstall database for phpmyadmin) and continue normally without changing any value. If you want to change some value do it in the file that you have edited before.

When configuration window asks what you want to do with existing configuration file choose Keep the local version currently installed.

At this point you can check the differences and only those must exist that you made in the file.

MySQL behavior has changed here, so you have few options:

• Use older MySQL version prior this change
• Use Ubuntu packages which did revert this change (see https://bugs.launchpad.net/ubuntu/+source/dbconfig-common/+bug/1563274)
• Wait for fixing dbconfig-common, see https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=824537

Update: You can workaround this bug as described in answer from William Ardila.

I've searched the internet for hours but none worked for me except this.

After changing dbc_dbport='' to dbc_dbport='0' I still encountered some other problems.

If you are not able to continue the configuration process properly, follow these additional steps:

First, simply choose Abort.

Then login to mysql as root using the password you’ve defined when you installed MariaDB.

mysql -u root -p

Next, issue following command:

CREATE DATABASE phpmyadmin;

Then, issue following command: (Do not forget to replace changethispassword with your own password of choice.)

GRANT ALL ON phpmyadmin.* TO phpmyadmin@localhost IDENTIFIED BY 'changethispassword';

Exit mysql> using:

\q

Next, edit the database configuration:

sudo gedit /etc/phpmyadmin/config-db.php

Edit the dbpass parameter with the password you’ve just defined.

<?php
##
## database access settings in php format
## automatically generated from /etc/dbconfig-common/phpmyadmin.conf
## by /usr/sbin/dbconfig-generate-include
##
## by default this file is managed via ucf, so you shouldn't have to
## worry about manual changes being silently discarded.  *however*,
## you'll probably also want to edit the configuration file mentioned
## above too.
##
$dbuser='phpmyadmin';
$dbpass='changethispassword';
$basepath='';
$dbname='phpmyadmin';
$dbserver='localhost';
$dbport='';
$dbtype='mysql';

Replace changethispassword with your own and save. (It must've been already set correctly.)