Предыстория.
Ранее стоял Ubuntu 14.04. Обновлен до 16.04. Репы обновлены до xenial.
Скайп (из официальных реп.) работал.
Потом была поставлена бета skypeforlinux по
этим инструкциям. (Пред. версия была предварительно удалена.)
Решено было вернуться на 4ю версию. Снесли бету, убрали репозиторий скайпа.
На ставится. Не находит скайп.
Проверил на
другой Ubuntu (с подобной же историей, но без установки беты версии): В синаптике видно, что скайп доступен в разделе net/parnter. Фото:
А
здесь в синаптике не видно раздела net/parnter. Соответственно не видно и скайпа. Фото синаптика:
Соответственно и
apt search skype-bin на другой Ubuntu находит скайп, на этой - нет.
В итоге пришлось
скачать и установить пакет самостоятельно, исправить зависимости. Скайп есть, но что с Partner и что делать - не понятно.

/etc/apt/sources.list:
# deb cdrom:[Ubuntu 14.04.2 LTS _Trusty Tahr_ - Release amd64 (20150218.1)]/ trusty main restricted
# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://archive.ubuntu.com/ubuntu xenial main restricted
deb-src http://archive.ubuntu.com/ubuntu xenial main multiverse universe restricted #Added by software-properties
## Major bug fix updates produced after the final release of the
## distribution.
deb http://archive.ubuntu.com/ubuntu xenial-updates main restricted
deb-src http://archive.ubuntu.com/ubuntu xenial-updates main multiverse universe restricted #Added by software-properties
## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team. Also, please note that software in universe WILL NOT receive any
## review or updates from the Ubuntu security team.
deb http://archive.ubuntu.com/ubuntu xenial universe
deb http://archive.ubuntu.com/ubuntu xenial-updates universe
## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://archive.ubuntu.com/ubuntu xenial multiverse
deb http://archive.ubuntu.com/ubuntu xenial-updates multiverse
## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
deb http://archive.ubuntu.com/ubuntu xenial-security main restricted
deb-src http://archive.ubuntu.com/ubuntu xenial-security main multiverse universe restricted #Added by software-properties
deb http://archive.ubuntu.com/ubuntu xenial-security universe
deb http://archive.ubuntu.com/ubuntu xenial-security multiverse
## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
deb http://archive.canonical.com/ubuntu/ xenial partner
deb http://download.webmin.com/download/repository sarge contrib # заблокировано при обновлении до xenial
deb http://webmin.mirror.somersettechsolutions.co.uk/repository sarge contrib # заблокировано при обновлении до xenial
# deb http://archive.canonical.com/ xenial partner
# deb-src http://archive.canonical.com/ xenial partner
deb http://archive.ubuntu.com/ubuntu xenial-backports universe main multiverse restricted
