Unable to locate package phpmyadmin on Ubuntu Server 18.04

Question

Whenever I try to install phpmyadmin on my ubuntu server 18.04 I get the following errors

sudo apt install phpmyadmin php-mbstring php-gettext
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package phpmyadmin
E: Unable to locate package php-mbstring
E: Unable to locate package php-gettext

Most threads I ca find suggest reupdating and upgrading using apt, but doing so doesn't do anything, also I get that error on the fourth line

Err:5 http://ppa.launchpad.net/nijel/phpmyadmin/ubuntu bionic Release
  404  Not Found [IP: 91.189.95.83 80]
Hit:6 http://archive.ubuntu.com/ubuntu bionic-updates InRelease
Hit:7 http://download.webmin.com/download/repository sarge Release
Reading package lists... Done
E: The repository 'http://ppa.launchpad.net/nijel/phpmyadmin/ubuntu bionic Release' does not have a Release file.

Can someone help with this?

Solution

On the Ubuntu Server 18.04 the list of apt sources is rather short and secure. If you want to install phpmyadmin or autossh or number of other packages which are not supported in main sources list, you should adjust the sources list.

$ sudo apt edit-sources

You can use the following list:

deb http://archive.ubuntu.com/ubuntu/ bionic main restricted
deb http://archive.ubuntu.com/ubuntu/ bionic-updates main restricted
deb http://archive.ubuntu.com/ubuntu/ bionic universe
deb http://archive.ubuntu.com/ubuntu/ bionic-updates universe
deb http://archive.ubuntu.com/ubuntu/ bionic multiverse
deb http://archive.ubuntu.com/ubuntu/ bionic-updates multiverse
deb http://archive.ubuntu.com/ubuntu/ bionic-backports main restricted universe multiverse
deb http://security.ubuntu.com/ubuntu bionic-security main restricted
deb http://security.ubuntu.com/ubuntu bionic-security universe
deb http://security.ubuntu.com/ubuntu bionic-security multiverse

More information can be found here: handyman.dulare.com/ubuntu-18-04-bionic-unable-to-locate-package...