I am running a Zimbra 5.0.14 open source email server, serving around 15 users.
Recently my users reported that a lot of INCOMING mails are put into the junk folder. There was even once when an email from the same domain (that is, email@example.com to firstname.lastname@example.org) fell into the junk folder!!! Seems the antispam is now too powerful, and it troubled my users quite a lot.
I once tried whitelisting some domains by modifying the "/opt/zimbra/conf/amavisd.conf", adding sth like "'domain.com' => -10.0" Strange enough, the lines were gone now! I suspect the file was modified when the antispam daemon updates itself.
Any suggestions of amendment? And any suggestions of ways to learn how to tune the antispam detailed settings? I've searched in the wiki and it seems quite confusing. Wish you could give a helping hand