I'm trying to setup the email service in my ClearOS server. I started with enabling all email-related services, such as SMTP. IMAP, POP, Antispam, etc. Then, I tried to exchange emails between two local users defined in the server, mans and jo. No messages got delivered from either user to another! When reviewing the log, it seems that a program called "mailpostfilter" hinders emails delivery. Here is a sample log:

Sep 24 21:25:51 lan postfix/pickup[28375]: F19BC127E59: uid=2002 from=<jo>

Sep 24 21:25:52 lan postfix/cleanup[14663]: F19BC127E59: message-id=<20170924182551.F19BC127E59@mydomain.com>

Sep 24 21:25:52 lan postfix/qmgr[28376]: F19BC127E59: from=<jo@mydomain.com>, size=420, nrcpt=1 (queue active)

Sep 24 21:25:52 lan postfix/smtpd[14668]: connect from localhost[127.0.0.1]

Sep 24 21:25:52 lan postfix/smtpd[14668]: 2E531127E64: client=localhost[127.0.0.1]

Sep 24 21:25:52 lan postfix/cleanup[14663]: 2E531127E64: message-id=<20170924182551.F19BC127E59@mydomain.com>

Sep 24 21:25:52 lan postfix/qmgr[28376]: 2E531127E64: from=<jo@mydomain.com>, size=585, nrcpt=1 (queue active)

Sep 24 21:25:52 lan postfix/smtpd[14668]: disconnect from localhost[127.0.0.1]

Sep 24 21:25:52 lan postfix/pipe[14665]: F19BC127E59: to=<mans@mydomain.com>, relay=mailprefilter, delay=0.36, delays=0.13/0.01/0/0.22, dsn=2.0.0, status=sent (delivered via mailprefilter service)

Sep 24 21:25:52 lan postfix/qmgr[28376]: F19BC127E59: removed

Sep 24 21:25:52 lan amavis[29220]: (29220-01) ESMTP :10024 /var/lib/amavis/tmp/amavis-20170924T212552-29220-sipL2n9N: <jo@mydomain.com> -> <mans@mydomain.com> SIZE=585 Received: from mydomain.com ([127.0.0.1]) by localhost (lan.mydomain.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP for <mans@mydomain.com>; Sun, 24 Sep 2017 21:25:52 +0300 (+03)

Sep 24 21:25:52 lan amavis[29220]: (29220-01) Checking: STGoUvW5rXZQ [127.0.0.1] <jo@mydomain.com> -> <mans@mydomain.com>

Sep 24 21:25:52 lan amavis[29220]: (29220-01) p001 1 Content-Type: text/plain, size: 8 B, name:

Sep 24 21:25:52 lan amavis[29220]: (29220-01) spam-tag, <jo@mydomain.com> -> <mans@mydomain.com>, No, score=-1 tagged_above=-99 required=5 tests=[ALL_TRUSTED=-1] autolearn=ham autolearn_force=no

Sep 24 21:25:52 lan amavis[29220]: (29220-01) dkim: candidate originators: From:<jo@mydomain.com>

Sep 24 21:25:52 lan amavis[29220]: (29220-01) dkim: not signing, empty signing domain, From: <jo@mydomain.com>

Sep 24 21:25:53 lan postfix/smtpd[14716]: connect from localhost[127.0.0.1]

Sep 24 21:25:53 lan postfix/smtpd[14716]: 03E65127E59: client=localhost[127.0.0.1]

Sep 24 21:25:53 lan postfix/cleanup[14663]: 03E65127E59: message-id=<20170924182551.F19BC127E59@mydomain.com>

Sep 24 21:25:53 lan postfix/qmgr[28376]: 03E65127E59: from=<jo@mydomain.com>, size=1162, nrcpt=1 (queue active)

Sep 24 21:25:53 lan amavis[29220]: (29220-01) STGoUvW5rXZQ FWD from <jo@mydomain.com> -> <mans@mydomain.com>, BODY=7BIT 250 2.0.0 from MTA(smtp:[127.0.0.1]:10026): 250 2.0.0 Ok: queued as 03E65127E59

Sep 24 21:25:53 lan amavis[29220]: (29220-01) Passed CLEAN {RelayedInternal}, LOCAL [127.0.0.1]:43194 <jo@mydomain.com> -> <mans@mydomain.com>, Queue-ID: 2E531127E64, Message-ID: <20170924182551.F19BC127E59@mydomain.com>, mail_id: STGoUvW5rXZQ, Hits: -1, size: 585, queued_as: 03E65127E59, 773 ms

Sep 24 21:25:53 lan amavis[29220]: (29220-01) TIMING-SA total 506 ms - parse: 2.4 (0.5%), extract_message_metadata: 6 (1.2%), get_uri_detail_list: 0.44 (0.1%), tests_pri_-1000: 10 (2.0%), tests_pri_-950: 3.9 (0.8%), tests_pri_-900: 2.9 (0.6%), tests_pri_-400: 1.98 (0.4%), tests_pri_0: 384 (75.9%), check_dkim_adsp: 11 (2.3%), check_spf: 0.71 (0.1%), check_razor2: 310 (61.3%), check_pyzor: 0.45 (0.1%), tests_pri_500: 7 (1.3%), learn: 55 (10.8%), b_learn: 51 (10.0%), b_count_change: 7 (1.4%), get_report: 0.63 (0.1%)

Sep 24 21:25:53 lan postfix/smtp[14669]: 2E531127E64: to=<mans@mydomain.com>, relay=127.0.0.1[127.0.0.1]:10024, delay=0.9, delays=0.09/0.02/0.01/0.77, dsn=2.0.0, status=sent (250 2.0.0 from MTA(smtp:[127.0.0.1]:10026): 250 2.0.0 Ok: queued as 03E65127E59)

Sep 24 21:25:53 lan postfix/qmgr[28376]: 2E531127E64: removed

Sep 24 21:25:53 lan amavis[29220]: (29220-01) size: 585, TIMING [total 782 ms] - SMTP greeting: 9 (1%)1, SMTP EHLO: 1.6 (0%)1, SMTP pre-MAIL: 1.2 (0%)2, mkdir tempdir: 2.1 (0%)2, create email.txt: 0.5 (0%)2, SMTP pre-DATA-flush: 6 (1%)3, SMTP DATA: 31 (4%)7, check_init: 1.7 (0%)7, digest_hdr: 3.7 (0%)7, digest_body_dkim: 0.8 (0%)8, collect_info: 6 (1%)8, mkdir parts: 3.5 (0%)9, mime_decode: 19 (2%)11, get-file-type1: 30 (4%)15, parts_decode: 0.3 (0%)15, check_header: 0.8 (0%)15, AV-scan-1: 37 (5%)20, spam-wb-list: 0.9 (0%)20, SA msg read: 1.3 (0%)20, SA parse: 4.1 (1%)21, SA check: 501 (64%)85, decide_mail_destiny: 5 (1%)85, notif-quar: 0.8 (0%)86, fwd-connect: 36 (5%)90, fwd-mail-pip: 6 (1%)91, fwd-rcpt-pip: 0.5 (0%)91, fwd-data-chkpnt: 0.2 (0%)91, write-header: 0.9 (0%)91, fwd-data-contents: 0.1 (0%)91, fwd-end-chkpnt: 47 (6%)97, prepare-dsn: 2.8 (0%)98, report: 3.0 (0%)98, main_log_entry: 8 (1%)99, update_snmp: 4.3 (1%)100, SMTP pre-response: 0.8 (0%)100, SMTP response: 0.5 (0%)100, unlink-2-fi...

Sep 24 21:25:53 lan amavis[29220]: (29220-01) ...les: 0.6 (0%)100, rundown: 1.2 (0%)100

Sep 24 21:25:53 lan lmtp[14721]: Delivered: <20170924182551.F19BC127E59@mydomain.com> to mailbox: user.mans

Sep 24 21:25:53 lan lmtp[14721]: USAGE mans user: 0.005061 sys: 0.009111

Sep 24 21:25:53 lan postfix/pipe[14718]: 03E65127E59: to=<mans@mydomain.com>, relay=mailpostfilter, delay=0.45, delays=0.05/0.02/0/0.38, dsn=2.0.0, status=sent (delivered via mailpostfilter service)

Sep 24 21:25:53 lan postfix/qmgr[28376]: 03E65127E59: removed

I searched the forum and knew about an old bug caused by "mailpostfilter" with ClearOS 6.2. I also found a post recommending removing this program completely from the sever.

What do you think? Is it mailpostfilter that prevents delivering messages in my server or something else?

Thank you.