Causes for ticket suspension

TheSuspended Tickets viewdisplays messages describing the cause of suspension for each suspended email. The following table lists the possible descriptions in the view and what each one means. Email sent from side conversations can also be suspended.


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Summary: ◀▼
You can identify why tickets are suspended by reviewing specific causes such as anonymous requests, spam detection, email authentication failures, or exceeding CC limits. Understanding these causes helps you manage suspended tickets by verifying users, adjusting email settings, or removing blocklists. This ensures legitimate tickets are recovered and reduces disruptions in handling customer support requests.




The Suspended Tickets view displays messages describing the cause of
suspension for each suspended email. The following table lists the possible descriptions in
the view and what each one means. Email sent from side conversations can also be suspended.










Cause of suspension
Description
Solution




Anonymous request
The ticket was submitted by an anonymous user in your help center.
The end user can locate the verification email in their inbox and click the
link to verify their email and that they’re the submitter of the request (which
recovers the suspended ticket). If you don’t want tickets from anonymous users to
be suspended, you can turn off Verify anonymous requests. However, doing so
may allow your account to be used in email spam attacks. See Enabling anyone to submit tickets.



Automatic email processing failed
Although rare, you might see this if a system-wide email processing error
occurred.

Contact Zendesk Customer Support for further
assistance with this cause of suspension, or refer to this article for help.


Automated response mail
This is used when the email header indicates that the message is an
auto-generated email of any kind.
Zendesk does not support the un-suspended flow of automated emails into
Zendesk, including from custom built ticket forms. The API and
Channels Framework are the only channels that support programmatic creation and
updating of tickets. The following headers can lead to this cause of suspension:

X-Twitteremailtype
X-Mailing-Software
Precedence
Auto-Submitted
Autoresponder
X-Autoreply
X-Autorespond
X-Autoresponder
X-Auto-Response-Suppress
X-Tender
RT-Ticket
Kayako|MailChimp|Benchmail Agent|Clang|Autoresponder
cmWinServer
X-EviteMessageID
Delivered-To
X-NetSuite





Automated response mail, out of office
Out of office and vacation auto-generated response emails are suspended.
Out-of-Office replies represent a threat to automated email systems. These are
often suppressed by the sending domain, but should always be suspended if they do
arrive at Zendesk.


CCs/followers limit reached
A ticket can have no more than 48 email addresses included as CCs.
Delete unnecessary email addresses from the CC line.


Detected as email loop

If you receive a large number of emails from a single sender in a short period
of time, those emails are suspended and the sender's address is blocklisted for one
hour. This also happens to tickets that are sent from an address equal to your
default Reply To address.
Zendesk does not support the bulk creation of tickets via emails to Zendesk
from the same sender. The API and Channels Framework are the only channels that
support bulk creation of tickets.


Detected as spam
This email was flagged as spam by the Zendesk email detection filters. This
email may also be flagged as spam because it was sent from a suspended user. Some
messages, if flagged with very high confidence of spam, are rejected entirely and
will not appear in the Suspended tickets view.
Check if the user is suspended, and unsuspend if necessary. You can recover the
suspended ticket, which can help improve the sender's reputation going
forward.


Detected email as being from a system user
Email generated by a mail server (for example, messages sent from addresses
beginning with mail-daemon@ and postmaster@) are suspended because it is assumed
that they are not intended to be support requests.
Mail from these addresses will need to be sent from or redirected through
non-system addresses.


Email authentication failed
The email is spoofed. The email appears to have originated from someone or
somewhere other than the actual source. This can also occur when the sender of the
email is an agent and the sender or forwarding domain fails DMARC.
The sender of this email must be permitted to send mail from your domain.
Consider configuring SPF and DKIM for this sending source, or disabling Sender
Authentication in email channel settings. Contact Zendesk Customer Support for further
assistance.


Email for "noreply" address
The email address is a "no reply" email address, meaning that it is not
intended to receive email.
Most no-reply addresses are not intended to be responded to, and emails to
these accounts are frequently not checked. You may want to verify that your
responses to these addresses are reaching your customers. If a customer uses a
no-reply email address to contact you, you can add the no-reply email address to
your allowlist to reduce the likelihood of
suspension.



End user only allowed to update their own tickets
This indicates that an email response for the purpose of updating a ticket was
received from an address or user that is different from the original submitter's
email address. This might happen if the submitter forwarded the email to a different
email account or user and then an attempt to reply back to your Zendesk was made.
Multiple email addresses per user are supported but they must be added to the user's
profile.
You can add the user as a CC to the ticket, otherwise their update will create
a flagged comment.


Email is too large
The email sent by the end user exceeds the maximum size limit and was rejected
by the server.
The user can try resending the email at a smaller size. This limit is for the
email body itself and is separate from the attachment size limits.


Failed email authentication
The email did not pass DMARC authentication.
Disable DMARC authentication. See Authenticating incoming email using DMARC.


HTML attributes per element limit exceeded
Zendesk Support could not process the attached email because it contained too
many HTML attributes.
The user can try reducing the number of HTML element attributes and resending
the email.


Malicious pattern detected
Some part of this ticket's message matched a pattern that is frequently
associated with spam messages, or messages intended to steal information from
recipients.
If you see important messages suspended for this reason, contact Zendesk Customer Support.


Malware detected
This indicates that possible malware or a malicious URL was detected.
The user can scan the attachment or links for malicious intent before
resending. Alternatively, resend the email without the attachment or suspect
URL.


Permission denied due to unauthenticated email update
This indicates that the email header doesn't contain the email token
identifying the ticket. This can happen if an email client strips out email header
information.
Verify that no headers are being removed by the forwarding mail server and that
the body is intact. Contact Zendesk Customer Support if you're still seeing
issues.


Permission denied for unknown email submitter
When you require your users to register and create an account, email received
from unregistered (unknown) users is suspended.
If you have a known customer base, consider importing your customer base prior
to them submitting tickets. See Bulk importing users.


Received from support address
The email was sent by (not forwarded from) one of your support
addresses.
The email was received from one of your listed support addresses and is causing
a mail loop. You will need to change the from: and reply-to: addresses in your email
client to show the actual requester's email address.


Sender or domain is on the blocklist
The ticket came from an address or domain that you've blocked.
If you need to accept these tickets, you can remove the address or domain from
the blocklist (see Using the allowlist and blocklist to control access to Zendesk
Support).


Sender domain not on allowlist
When your account is configured to allow emails from only a given set of
domains (using the allowlist), this indicates that the sender's email address or
domain is not within that set.
You need to allow the email domain or address (see Using the allowlist and blocklist to control access to Zendesk
Support).


Submitted by unverified user
This indicates that the user is known, but has not yet verified their email
address.
The end user must verify their email address with the verification email sent
to them. An agent or admin can also manually verify the email on the user's profile
or resend the verification email.


Submitted by unverified account owner
The account owner never clicked the link within the verification email to
verify their account. Zendesk sends this email to the account owner when the account
is created or when a new owner or owner email address is added to the
account.
The account owner can locate the email in their inbox and click the link to
verify the address. Alternatively, you can resend the verification email.


User does not have authority to update the
ticket
Someone tried to reply to an existing Zendesk ticket, but Zendesk did not
recognize them as the Requester or a CC on that ticket.
You can add the user as a CC to the ticket. Otherwise, their update will create
a flagged comment.


User must sign up to submit email, user notified
This is used when an account requires end users to register and therefore
verify their email address before submitting tickets (see Permitting only users with approved email addresses to submit
tickets). Once their email address/user account is verified, they can
submit tickets.
The user is prompted to register for access. Once the user registers, their
suspended ticket turns into a normal ticket without any action from an admin
required.






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