An email address or a phone number can be quarantined, for example, when the mailbox is full or if the address does not exist.
In any case, the quarantine procedure complies with specific rules described in this section.
The profiles whose email addresses or phone number are in quarantine are automatically excluded during message preparation (see Identifying quarantined addresses for a delivery). This will speed up deliveries, as the error rate has a significant effect on delivery speed.
Some internet access providers automatically consider emails to be spam if the rate of invalid addresses is too high. Quarantine therefore allows you to avoid blacklisting by these providers.
Moreover, quarantines help reducing SMS sending costs by excluding erroneous phone numbers from deliveries.
For more on best practices to secure and optimize your deliveries, refer to this page.
Quarantine applies only to an address, not the profile itself. It means that, if two profiles have the same email address, they will both be affected if the address is quarantined.
Likewise, a profile whose email address is quarantined could update his profile and enter a new address, and could then be targeted by delivery actions again.
Blacklisting, on the other hand, will result in the profile no longer being targeted by any delivery, for example after an unsubscription (opt-out). For more on the blacklisting process, refer to Managing blacklisting in Campaign.
When a user replies to an SMS message with a keyword such as "STOP" in order to opt-out from SMS deliveries, his profile is not blacklisted like in the email opt-out process. The profile phone number is sent to quarantine with the Blacklisted status. This status refers to the phone number only, the profile is not blacklisted so that the user continues receiving email messages. For more on this, refer to this section.
If you need to remove an address from quarantine, contact your technical administrator.
Administrators can list the addresses in quarantine for the entire platform from the Administration > Channels > Quarantines > Addresses menu.
This menu lists quarantined elements for email, SMS and Push notification channels.
The increase in number of quarantines is a normal effect, related to the "wear and tear" of the database. For example, if the lifetime of an email address is considered to be three years and the recipient table increases by 50% each year, the increase in quarantines can be calculated as follows: End of Year 1: (1*0.33)/(1+0.5)=22%. End of Year 2: ((1.22*0.33)+0.33)/(1.5+0.75)=32.5%.
Soft error: soft errors do not send immediately an address to quarantine, but they increment an error counter. When the error counter reaches the limit threshold, the address goes into quarantine. In the default configuration, the threshold is set at five errors, where two errors are significant if they occur at least 24 hours apart. The address is placed in quarantine at the sixth error. The error counter threshold can be modified. For more on this, refer to Retries after a delivery failure.
If a user qualifies an email as a spam (Feedback loop), the message is automatically redirected towards a technical mailbox managed by Campaign. The user's email address is then automatically sent to quarantine with the Blacklisted status. This status refers to the address only, the profile is not blacklisted, so that the user continues receiving SMS messages and push notifications.
In the list of quarantined addresses (see Identifying quarantined addresses for the entire platform), the Error reason field indicates why the selected address was placed in quarantine.