Email non-delivery and complaints

Non-deliveries and complaints highlight issues with your email delivery. Addressing them promptly helps protect recipient experience and improve your sending practices.

Non-delivery activities:

  • Bounced Email (Hard and Soft Bounces)
  • Invalid Email
  • Deferred Email
  • Complaints

Managing these issues is crucial for maintaining good email deliverability. High rates of non-delivery and complaints can harm your sender reputation. Follow deliverability best practices to ensure your emails reach your audience's inbox.

Learn more about Improving email deliverability.


Email non-delivery activities

Email non-delivery can happen due to issues with either the email content or the recipient’s side. Here’s a breakdown:

  • Invalid Email: An Invalid email activity is triggered before the email is sent. Invalid emails are tracked separately and not counted in the Sent email activity.
  • Bounced Email: This happens when the email is rejected by the recipient’s mail server. Bounced emails are counted in the Sent email activity but also tracked separately.
  • Deferred Email: This is when the email is temporarily delayed but not rejected. Deferred emails are also counted in the Sent email activity and tracked separately.
  • Complaints: If a recipient marks your email as spam, it is recorded as a complaint.

You can view email non-delivery activity under Activities and in Reports.


Bounced email (hard and soft bounces)

When an email can’t be delivered, it bounces back. Bounces fall into two categories: hard and soft.

Hard bounces

A hard bounce occurs when an email is permanently rejected because the address is invalid or doesn’t exist. Common causes include:

  • Spelling errors in the email address
  • A closed or inactive mailbox

When an email hard bounces, the address is automatically unsubscribed from future mailings to protect your sender reputation. This prevents you from repeatedly sending emails to invalid addresses, which could harm your reputation and reduce your chances of reaching your recipients' inboxes.

Soft bounces

A soft bounce happens when an email is temporarily rejected but the address is likely valid. Typical reasons include:

  • Temporary server issues
  • Recipient’s mailbox being full
  • Temporary blocks or filters

Soft bounces are less permanent than hard bounces. They might result from temporary problems like server outages or your IP address being temporarily blocked.

Most bounces in your Ortto account are not due to IP blocks, thanks to the sending limitations around our acceptable usage policy  and the efforts of our Deliverability team.

However, if you notice a pattern of bounces or suspect a block, contact our Support team at help@ortto.com for assistance.

Manually resubscribe a person

If you need to fix an email address that caused a hard bounce (e.g., due to a spelling error), you can manually resubscribe the person. This should only be done if you've corrected the email address.

CAUTION: Be cautious when resubscribing. Continually emailing addresses that have hard-bounced can harm your sender reputation.

Learn more about editing a person’s subscription preferences under Viewing and editing a person.


Invalid email

An Invalid email activity is triggered before the email is sent. Reasons for an invalid email include:

  • the content of the email was empty
  • a permanent delivery issue occurred with a previous attempt to this subscriber
  • various unsubscribe activities
  • the subscriber's email value was empty (e.g. you used a merge tag with no default value).

NOTE: Invalid email activity doesn’t have a retention limit and is tracked for the life of your Ortto account.

Invalid email statuses

Here’s a quick guide to the Invalid Email statuses:

  • Drop (Dropped): This means the email was dropped by Ortto before reaching the mail server. We don’t receive bounces for these drops. Drops help protect your sender reputation by preventing mail servers from recording your sends as hard bounces or spam.
  • Suppression List: Ortto uses SendGrid, which maintains a suppression list to safeguard both Ortto’s and your sender reputation.

NOTE: Most invalid email statuses will automatically suppress the contact’s email address. Therefore, using a suppression filter for invalid emails is usually not needed.

Invalid email status

Description

Contact was unsubscribed

Contact was unsubscribed and attempted to be sent to.

Dropped: Bounced address

The address hard bounced at least once and is now on a bounced suppression list handled by SendGrid.

Dropped: Invalid

Likely typo or non-existent domain addresses for major providers. For example, hello@gmai.com.

Some of these types of domain misspellings have been connected with spam traps (email addresses designed to look like real email addresses, created by spammers), and so are dropped as a safety measure.

Dropped: Spam reported address

The recipient has previously reported one of your emails as spam and their address is now on a suppression list handled by SendGrid.

Duplicate

Is related to repeated attempts at triggering the same send (i.e. an address that has already been sent a particular campaign). Can be related to the same contact record repeatedly triggering an automation such as a journey that’s already been successfully triggered and delivered or due to multiple contact records with the same email address.

TIP: If a contact has multiple records with the same email, the term "duplicate" may appear for each additional record that enters the journey.

Email prevention limit reached

The email limit set in your account has been reached so the recipient was not sent a particular email (also captured as the Skipped email activity).

Invalid

By default a non-functioning email address format. For example, hello @ortto.com where there is a space in the email address causing the problem.

Temp-error

It is usually related to a one-time experience and doesn’t cause issues for future campaign attempts to that address. This may be related to an error with the API that handles email sends.

If you are using a suppression filter for Invalid email, we don’t recommend adding Temp-error email addresses, as these are likely ok to use.

Missing from email

The "from" email was missing at the time the email was sent. This might happen if you use a merge tag to populate the From email address field and the email value is invalid, for example.

Fatal-error

The email was missing a subject line at the time the email was sent, and was rejected by SendGrid.

Missing JSON document

The email was configured to use dynamic content at a "per contact" request level and the contact's ID was missing from the JSON endpoint. As a result, the email was not sent to that contact.

Invalid unsubscribe header

The unsubscribe link or/and the unsubscribe mailto email are invalid.

Unsubscribe link: It must be a valid URL (the structure needs to be correct) and non-encoded.

Unsubscribe mailto email: It must contain a valid and non-encoded email address.

NOTE: This only applies to Enterprise customers who use their own unsubscribe details. If you are an Enterprise customer and would like to have this feature enabled, please contact our Support team.

IMPORTANT:

If you think an email address is invalid due to a typing error (e.g., hello@gmai.com instead of hello@gmail.com), you should not attempt to edit it in the person’s profile without their permission. Communications are authorized only for the email address originally provided.

Editing and sending emails to a corrected address without consent can lead to:

  • Sending messages to someone who hasn’t agreed to receive them at the new address.
  • Incorrectly editing the email address and sending messages to an unintended recipient.

Sending emails to recipients who haven’t consented can result in them marking your emails as spam, which can harm your sender reputation.

Correcting email address errors

To fix what might be a typing error in an email address, follow these steps:

  1. Collect the correct email address: Contact the person to confirm their correct email address and obtain their permission to update it. Alternatively, ask them to resubmit their email address and consent via a form on your website.
  2. Prevent future errors: Add a "Confirm email address" field to your forms. This allows users to double-check their email address before submission.

This approach ensures accuracy and consent while preventing issues with misspelled email addresses.


Deferred email

A deferred email means the recipient’s mail server has temporarily refused delivery. Ortto will keep trying to deliver the email for up to 72 hours.

If the email is successfully delivered within that time, it will be recorded as a Sent email. If delivery fails after 72 hours, it will be marked as a Bounced email.


Complaints

Complaints occur when recipients mark your email as spam. They signal that the email was unwanted or irrelevant. High complaint rates can damage your sender reputation.

The acceptable complaint rate for permission-based senders is below 0.02%, or fewer than 2 out of every 10,000 subscribers.

IMPORTANT: When someone marks your email as spam, they are automatically unsubscribed from all future emails.

If you notice a rise in complaints above this threshold, stop sending emails and review your audience's subscription preferences. Frequent complaints suggest recipients feel they are receiving unwanted emails, which can negatively impact your sender reputation.