Open source alternative for microsoft exchange
There are so many different open source Microsoft exchange/365 alternatives out there (Zimbra, Open X Change, Kolab, Citadel). I want to know, out of all of the open source Microsoft exchange alternatives that are out there, which is the most secure (suffers lesa from vulnerabilities) but also provides with the most features that microsoft exchange has.
Right now I have Postfix/Dovecot with roundcube as my mail server (running centos 6.5) and it does the job (except has no calendar support).
Last edited by Altiris; 04-15-2014 at 10:50 AM.