dovecot-core software package provides secure POP3/IMAP server - core files, you can install in your Ubuntu 16.10 (Yakkety Yak) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install dovecot-core
dovecot-core is installed in your system.
Make ensure the dovecot-core package were installed using the commands given below,
$ sudo dpkg-query -l | grep dovecot-core *
You will get with dovecot-core package name, version, architecture and description in a table
| Distro | Ubuntu 16 10 yakkety yak |
| Section | |
| Package | dovecot-core |
| Version | 1:2.2.24-1ubuntu1 |
| Description | secure POP3/IMAP server - core files |
| Sub Section |