Suspended tickets

When an email is received by Zendesk, a series of processing rules are executed. For example, there's a rule to determine to which account this email belongs, and another rule which determines if this is a spam email.

Four things can happen to an email received by Zendesk:

1. A ticket gets created or updated. This happens in most cases, and does so when a valid email has been received.
2. A bounce email gets sent back. This happens when a user tries to update a closed ticket, or an account has exceeded its limitations.
3. A suspended ticket gets created. This happens when the email violates a processing rule (more on this below).
4. A hard reject, email gets silently refused by Zendesk. This only happens in the single case where there's a 99.9% probability of the email being spam.

The interesting part of the ticket processing engine, is item 3 in the above. We run a series of tests and validations to ensure that the inbound email is indeed valid, and if not, we suspend it.

Causes of suspension

We operate with the following causes of suspension:

Detected as spam The email has been determined to be spam with high probability (but less than the 99.9% mentioned above).

Sender domain not on whitelist Your account is configured to only allow emails from a given set of domains, and the sender domain is not within that set.

Submitted by unverified user The user sending the email has not yet clicked the verification link in his welcome email.

Automated response mail Emails sent by auto mailers that have set a header in the mail, telling us that this is an auto geneated response email.

Detected as mail loop If a sender exceeds a threshold by sending a large number of emails to your account within a small time frame, the sender address gets blacklisted for an hour, and emails received in this interval become suspended tickets.

Unknown user tried to update existing ticket Someone tried to send an update to an existing ticket without having an account in Zendesk.

End user only allowed to update their own tickets An end user tried to update a ticket which was not submitted by himself.

Automated response mail, delivery failed If an email sent from your account got rejected somewhere in the email delivery mechanism.

Automated response mail, out of office An email sent from your account to an end user resulted in an "out of office" or "vacation" email, suspend this notice.

Detected email as being from a system user When the sender is another mail server (typically mail-daemon@something or postmaster@something) odds are that this mail was not intended to become a ticket.

Permission denied for unknown email submitter Accounts that are configured to not accept email from anyone will get this cause of suspension when the sender does not exist in Zendesk.

User must sign up to submit email, user notified Accounts that are configured to accept email from anyone will get this cause of suspension. Note, a verification link has been sent to the user, so most likely, you should not handle this type of suspension manually.

Got an itch?

We strive to make the Zendesk email integration absolutely world class. But as you probably know from your own private inbox, spam and email abuse is tough challenge. If a sender of an email is not polite and does not set correct information in the email, we're left to determine whether en email is valid purely by evaluating its structure and content.

If there's something you would like handled (or handled differently) in the email processing system, don't hesitate to let us know.