Hello!
I encountered a problem: the old version of iRedMail cannot be installed. Installation is on CentOS Linux release 7.9.2009 (Core).
I know that the version is old, but at the moment you need to set up a mail server on it.
Thanks.

Package dos2unix-6.0.3-7.el7.x86_64 already installed and latest version
Package logwatch-7.4.0-35.20130522svn140.el7_5.noarch already installed and latest version
Package lz4-1.8.3-1.el7.x86_64 already installed and latest version
Nothing to do
< SKIP > Function: after_package_installation.

********************************************************************
* Start iRedMail Configurations
********************************************************************
< SKIP > Function: generate_ssl_keys.
[ INFO ] Create required system accounts.
< SKIP > Function: add_user_vmail.
< SKIP > Function: add_user_mlmmj.
< SKIP > Function: add_user_iredadmin.
< SKIP > Function: add_user_iredapd.
< SKIP > Function: web_server_config.
< SKIP > Function: mysql_setup.
< SKIP > Function: postfix_setup.
< SKIP > Function: dovecot_setup.
< SKIP > Function: mlmmj_config.
< SKIP > Function: mlmmjadmin_config.
< SKIP > Function: clamav_config.
< SKIP > Function: amavisd_config.
< SKIP > Function: sa_config.
< SKIP > Function: iredapd_setup.
< SKIP > Function: iredadmin_setup.
< SKIP > Function: fail2ban_config.
< SKIP > Function: rcm_setup.
< SKIP > Function: cleanup.