SoGo (EAS): Mails stay forever in outbox, if you send to non-existent INTERNAL email-adress

[jmber]

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Description

Hi, this BUG was also reported to SoGO. https://www.sogo.nu/bugs/view.php?id=4270

Perhaps the Mailcow-Postfix sends a wrong signal back to SoGo? This problems only appears for internal DOMAINS, if the email-adress does not exists.

If it is an external "wrong" eMail-address, it works.

Logs

Log: "sogod[67:67] SMTP(RCPT TO) error: 5.1.1 [email protected]: Recipient address rejected: User unknown in virtual mailbox table

Steps to reproduce

1. Open eMail Client with ActiveSync config (Outook, Gmail, ....)
2. write an email to an internal mailcow-user, who does not exist. for example: [email protected]
3. email get stuck in outlook, without a error ...

System information

| My operating system | Ubuntiu 20.04 | | Is Apparmor, SELinux or similar active? | no | | Virtualization technlogy (KVM, VMware, Xen, etc - LXC and OpenVZ are not supported | no |

[jmber]

Workaround:

disable smtpd_reject_unlisted_recipient in postfix.

master.cf

add this config before line: https://github.com/mailcow/mailcow-dockerized/blob/5613134fed7385176a63edcf1ab71ce994200f0e/data/conf/postfix/master.cf#L52 -o smtpd_reject_unlisted_recipient=no # SoGo Fix

[gimmebackdabana]

I can confirm this behaviour also on em Client (V9) but without EAS (configured through autodiscover IMAP, CalDAV, CardDAV, SMTP).

Adding

-o smtpd_reject_unlisted_recipient=no # SoGo Fix

before line 52 in master.cf, followed by docker compose down and docker compose up -d didn't help.

em Client throws an error in a popup message (German version):

[SMTP] Die Nachricht (Der E-Mail-Empfänger wurde vom Server nicht akzeptiert.) kann nicht gesendet werden

After that the message stays in outbox.

[milkmaker]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.