imap-server software package provides virtual package provided by mailutils-imap4d, dovecot-imapd, courier-imap, cyrus-imapd, citadel-server, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install imap-server
imap-server is installed in your system.
Make ensure the imap-server package were installed using the commands given below,
$ sudo dpkg-query -l | grep imap-server*
You will get with imap-server package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | Virtual packages |
| Package | imap-server |
| Version | |
| Description | virtual package provided by mailutils-imap4d, dovecot-imapd, courier-imap, cyrus-imapd, citadel-server |
| Sub Section | Virtual |