Troubleshooting Bounces
Select each of the following common bounce reasons to learn recommended actions for addressing a campaign with a spike in bounces of that recipientState.
My campaign had a high bounce rate! Why?
MailBlockGeneral
Suppressed
HardBounce
SoftBounceGeneral
MailBoxFull
HardBounce
Too many hard bounces means there was a spike in invalid emails in your audience. Iterable will automatically unsubscribe the users that hard bounced, but to make sure you're minimizing hard bounces in the future, you should:
Identify the source of the invalid emails to improve your data hygiene. Did you accidentally send to an old list? Are you sending to any purchased lists to users who have opted in? Have your web sign up forms been set up to prevent bot sign-ups? Consider using an email validation tool if you are not already doing so.
Back to Bounce Menu
MailBlockGeneral
Too many MailBlockGeneral soft bounces means there is an active block or reputation issue from at least one mailbox provider. This can be due to a number of reasons and you'll need to investigate a little further to determine what the best next move is. To address a mail block issue, you should:
Suppress users who bounced due to a mail block until the issue is resolved. This will prevent further harm to your sending reputation. Identify which mailbox provider is causing the issue. Analyze whether you're failing due to complaints, poor reputation, or if any changes to your DNS have caused any authentication failure (SPF, DKIM, DMARC). Use a blocklist checker such as MXToolbox to identify if your IP or sending domain are on any blocklists. If so, follow the process for the specific blocklist to request removal.
Back to Bounce Menu
Suppressed
Too many soft bounces due to being Suppressed means that the email is on the ESP suppression list because of a past complaint or hard bounce.
Only remove users from the suppression list if they have requested to receive emails again. If you need help removing someone from an ESP suppression list, reach out to Iterable's support team
Suppress these users from future sends to ensure they don't continue to bounce and harm your reputation.
Back to Bounce Menu
SoftBounceMailboxFull
Too many SoftBounceMailboxFull bounces can indicate that the audience you're sending too is largely inactive. To address this:
Consider adjusting your soft bounce maintenance policy to be more strict for SoftBounceMailboxFull bounces. If a user's mailbox is full, they are unlikely to get more space. You may want to use segmentation and journeys to unsubscribe them from emails sooner if you are seeing spikes in these bounces.
Back to Bounce Menu
SoftBounceGeneral
Too many soft bounces with a SoftBounceGeneral means that Iterable can't determine the exact reason for a delivery failure with the data provided. In this case, further investigation is needed, including:
Export the bounces from the campaign to view the bounceMessage field and investigate further. Determine next steps based on whether the issue is a reputation issue or if it is more temporary. If you cannot find more information about the bounce, consider if your soft bounce maintenance policy should be stricter.
Back to Bounce Menu
Troubleshooting Bounces
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Transcript
Troubleshooting Bounces
Select each of the following common bounce reasons to learn recommended actions for addressing a campaign with a spike in bounces of that recipientState.
My campaign had a high bounce rate! Why?
MailBlockGeneral
Suppressed
HardBounce
SoftBounceGeneral
MailBoxFull
HardBounce
Too many hard bounces means there was a spike in invalid emails in your audience. Iterable will automatically unsubscribe the users that hard bounced, but to make sure you're minimizing hard bounces in the future, you should:
Identify the source of the invalid emails to improve your data hygiene. Did you accidentally send to an old list? Are you sending to any purchased lists to users who have opted in? Have your web sign up forms been set up to prevent bot sign-ups? Consider using an email validation tool if you are not already doing so.
Back to Bounce Menu
MailBlockGeneral
Too many MailBlockGeneral soft bounces means there is an active block or reputation issue from at least one mailbox provider. This can be due to a number of reasons and you'll need to investigate a little further to determine what the best next move is. To address a mail block issue, you should:
Suppress users who bounced due to a mail block until the issue is resolved. This will prevent further harm to your sending reputation. Identify which mailbox provider is causing the issue. Analyze whether you're failing due to complaints, poor reputation, or if any changes to your DNS have caused any authentication failure (SPF, DKIM, DMARC). Use a blocklist checker such as MXToolbox to identify if your IP or sending domain are on any blocklists. If so, follow the process for the specific blocklist to request removal.
Back to Bounce Menu
Suppressed
Too many soft bounces due to being Suppressed means that the email is on the ESP suppression list because of a past complaint or hard bounce.
Only remove users from the suppression list if they have requested to receive emails again. If you need help removing someone from an ESP suppression list, reach out to Iterable's support team
Suppress these users from future sends to ensure they don't continue to bounce and harm your reputation.
Back to Bounce Menu
SoftBounceMailboxFull
Too many SoftBounceMailboxFull bounces can indicate that the audience you're sending too is largely inactive. To address this:
Consider adjusting your soft bounce maintenance policy to be more strict for SoftBounceMailboxFull bounces. If a user's mailbox is full, they are unlikely to get more space. You may want to use segmentation and journeys to unsubscribe them from emails sooner if you are seeing spikes in these bounces.
Back to Bounce Menu
SoftBounceGeneral
Too many soft bounces with a SoftBounceGeneral means that Iterable can't determine the exact reason for a delivery failure with the data provided. In this case, further investigation is needed, including:
Export the bounces from the campaign to view the bounceMessage field and investigate further. Determine next steps based on whether the issue is a reputation issue or if it is more temporary. If you cannot find more information about the bounce, consider if your soft bounce maintenance policy should be stricter.
Back to Bounce Menu