550 Verification failed Sender verify failed (in reply to RCPT TO command)

Note: email addresses, domains, and ip addresses have been changed to protect the innocent

Current Error:

Apr 28 23:47:32 vps01 postfix/smtp[8012]: 2A03D6285EF9: to=<[email protected]>, relay=mail.somedomain.com[162.144.93.233]:25, delay=42, delays=0.01/0.02/21/21, dsn=5.0.0, status=bounced (host mail.somedomain.com[162.144.93.233] said: 550-Verification failed for <[email protected]> 550-The mail server could not deliver mail to [email protected]. The account or domain may not exist, they may be blacklisted, or missing the proper dns entries. 550 Sender verify failed (in reply to RCPT TO command))

I am trying to get email working for a client with several domains on a vps running Ubuntu Server and Apache2. Server has IspConfig 3 installed if it makes any difference to anybody.

I am able to receive and send emails to most of the domains that I have tried so far except one in particular. Others are probably failing that are unknown to me.

I was receiving an error 550 Access denied - Invalid HELO name (See RFC2821 4.1.1.1) but I have been able to fix that as far as I know by creating rDNS record and changing my hostname in postfix to my FQDN. This has proceeded to my current error.

I have followed the guide at https://www.howtoforge.com/hardening-postfix-for-ispconfig-3 to harden my postfix to prevent spam.

I have reviewed Postfix Sender Verification 550 and checked my MX records but it appears to me that everything is set correctly.

dig mydomain.org MX

; <<>> DiG 9.9.5-9ubuntu0.5-Ubuntu <<>> mydomain.org MX
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 18363
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;mydomain.org.             IN      MX

;; ANSWER SECTION:
mydomain.org.      1199    IN      MX      10 55.55.55.55. (ip address changed for security purposes)

;; Query time: 44 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Thu Apr 28 23:54:59 CDT 2016
;; MSG SIZE  rcvd: 75

I have been using http://mxtoolbox.com/SuperTool.aspx?action=smtp%3amydomain.org&run=toolpage# to check for problems along the way as well, but the only insight it is giving me know appears to be longer connection and transaction time which I believe is due to configuring postscreen.

Full mail.log for time period during errors

Apr 29 00:24:44 vps01 postfix/smtpd[9021]: connect from localhost.localdomain[127.0.0.1]
Apr 29 00:24:44 vps01 postfix/smtpd[9021]: DA4326285EF9: client=localhost.localdomain[127.0.0.1]
Apr 29 00:24:44 vps01 postfix/cleanup[9013]: DA4326285EF9: message-id=<[email protected]>
Apr 29 00:24:44 vps01 postfix/smtpd[9021]: disconnect from localhost.localdomain[127.0.0.1]
Apr 29 00:24:44 vps01 postfix/qmgr[7860]: DA4326285EF9: from=<[email protected]>, size=1671, nrcpt=1 (queue active)
Apr 29 00:24:44 vps01 amavis[8496]: (08496-10) Passed CLEAN {RelayedOpenRelay}, <[email protected]> -> <[email protected]>, Message-ID: <[email protected]>, mail_id: aJjfGa_rtNVH, Hits: -0.101, size: 1145, queued_as: DA4326285EF9, dkim_sd=dkim:mydomain.org, 399 ms
Apr 29 00:24:44 vps01 postfix/smtp[9018]: 669CD6285BEA: to=<[email protected]>, relay=127.0.0.1[127.0.0.1]:10024, delay=0.5, delays=0.08/0.02/0/0.4, dsn=2.0.0, status=sent (250 2.0.0 from MTA(smtp:[127.0.0.1]:10025): 250 2.0.0 Ok: queued as DA4326285EF9)
Apr 29 00:24:44 vps01 postfix/qmgr[7860]: 669CD6285BEA: removed
Apr 29 00:25:01 vps01 postfix/postscreen[9069]: CONNECT from [::1]:44502 to [::1]:25
Apr 29 00:25:01 vps01 postfix/postscreen[9069]: WHITELISTED [::1]:44502
Apr 29 00:25:01 vps01 postfix/smtpd[9071]: connect from localhost[::1]
Apr 29 00:25:01 vps01 postfix/smtpd[9071]: lost connection after CONNECT from localhost[::1]
Apr 29 00:25:01 vps01 postfix/smtpd[9071]: disconnect from localhost[::1]
Apr 29 00:25:27 vps01 postfix/smtp[9022]: DA4326285EF9: to=<[email protected]>, relay=mail.somedomain.com[162.144.93.233]:25, delay=43, delays=0.01/0.01/22/21, dsn=5.0.0, status=bounced (host mail.somedomain.com[162.144.93.233] said: 550-Verification failed for <[email protected]> 550-The mail server could not deliver mail to [email protected].  The account or domain may not exist, they may be blacklisted, or missing the proper dns entries. 550 Sender verify failed (in reply to RCPT TO command))
Apr 29 00:25:27 vps01 postfix/cleanup[9013]: D2C3E6285EFA: message-id=<[email protected]>
Apr 29 00:25:27 vps01 postfix/qmgr[7860]: D2C3E6285EFA: from=<>, size=4219, nrcpt=1 (queue active)
Apr 29 00:25:27 vps01 postfix/bounce[9112]: DA4326285EF9: sender non-delivery notification: D2C3E6285EFA
Apr 29 00:25:27 vps01 postfix/qmgr[7860]: DA4326285EF9: removed
Apr 29 00:25:27 vps01 dovecot: lda([email protected]): sieve: msgid=<[email protected]>: stored mail into mailbox 'INBOX'
Apr 29 00:25:27 vps01 postfix/pipe[9113]: D2C3E6285EFA: to=<[email protected]>, relay=dovecot, delay=0.06, delays=0.01/0.02/0/0.03, dsn=2.0.0, status=sent (delivered via dovecot service)
Apr 29 00:25:27 vps01 postfix/qmgr[7860]: D2C3E6285EFA: removed
Apr 29 00:25:28 vps01 postfix/anvil[8945]: statistics: max connection rate 1/60s for (smtpd:64.20.227.137) at Apr 29 00:22:05
Apr 29 00:25:28 vps01 postfix/anvil[8945]: statistics: max connection count 1 for (smtpd:64.20.227.137) at Apr 29 00:22:05
Apr 29 00:25:28 vps01 postfix/anvil[8945]: statistics: max message rate 1/60s for (smtpd:64.20.227.137) at Apr 29 00:22:07
Apr 29 00:25:28 vps01 postfix/anvil[8945]: statistics: max cache size 1 at Apr 29 00:22:05

It appears that I did not receive the RCPT TO command to verify the user. I have researched online that trying to resolve this is a waste of time and should just tell the receiving domain to turn off verifying users but this is not an available option.

UPDATE

OK, I have made the DNS changes and new mx record host @ points to mail.mydomain.org. I have already created A record for mail to point to my ip address. I will wait for dns to propogate and try again.