Email isn't sending or receiving
SummitPSA's email engine has two halves: outbound (SMTP, used for ticket reply notifications and auto-acknowledgements) and inbound (IMAP polling and/or the Mailgun webhook, which turn email into tickets and replies). Symptoms differ by half.
Outbound mail isn't being sent
Outbound send picks the first active email account that has an SMTP host configured. If no such account exists, every send helper silently returns without sending. Check that you have an active account with SMTP host, port, credentials, and TLS settings filled in. A reply notification is also skipped when the ticket's contact has no email address.
On the isolated demo instance only, all outbound email is force-disabled by design. This does not apply to your self-hosted install.
Inbound IMAP isn't creating tickets
The poller only processes accounts that are active and have an IMAP host set. It reads UNSEEN messages from the configured folder (default INBOX) and marks them \Seen after processing. Use the account's Test connection action to verify credentials; failures are stored on the account's last_error field. Password and Microsoft 365 OAuth2 auth are both supported (M365 Basic Auth was deprecated September 2025).
Some emails are ignored on purpose
To prevent auto-reply loops, the engine skips messages whose sender looks automated (mailer-daemon, no-reply, postmaster, bounce, etc.) or whose subject matches phrases like delivery status notification, out of office, or automatic reply. Duplicate messages (same Message-ID) are also skipped. These show as ignored or are silently deduped.
Replies create new tickets instead of threading
Threading relies on the ticket reference [T-NNNNN] in the subject line, and threads onto tickets that are open, in progress, or waiting (on the customer or a third party). If a client strips the tag, or the ticket is closed or resolved, a new ticket is created instead.
Mailgun inbound webhook
The /api/inbound/mailgun endpoint returns 503 until the Mailgun signing key and an SMTP-configured account anchor are both present, and 406 for a bad/forged HMAC signature. A misconfigured signing key is the usual cause of inbound mail never arriving.