When an email is rejected by your subscriber's email server- it's called a bounce. It basically an email that never arrives in the recipient's inbox and is sent back.

There are many reasons an email address may bounce, below are some common reasons this could happen.

• Domain name does not exist
• Recipient email address does not exist
• Recipient email server has completely blocked delivery
• The email cannot be delivered due to an issue with the receiving server.
• The email has been delivered, but the recipient has an auto-reply enabled on their account. (Soft bounce)
• The recipient's email server is blocking messages from your email account based on an email history or reputation that indicates you've been sending SPAM.

Step 1 Setup mailbox for the bounce back handling

• From the admin panel, navigate to jBounceback >> Mailboxes
• Create a Mailbox and fill in the correct mailbox information to be able to connect and process the emails automatically.
• Click save once you are done

Name: data-original-title="Name of the account, this name is not used to connect to the mailbox but enables you to sort your mailbox properly
Description: Write the description of your mailbox
Connection Method: Select the system of connection you want to use
Server: Address of the server you connect to. Example: imap.gmail.com
Secure Method: Define if the account requires secure connection or not
Self-asssigned Certificates: If you select "Yes", the system won't require the validation of certificates from TLS/SSL server. This option is needed if your server uses self-signed certificates.
Port: Port used to connect to the server
Username: Define the username used to connect to the mailbox. If Gmail is used, enter your gmail email.
Password: Define the password used to connect to the mailbox. If Gmail is used, enter your gmail password.

Parameters

Save the message: The system can save the message so you can easily see it if necessary.
Forward: Should the system forward the message (store in Inbox) to another e-mail address. If so, please specify the e-mail address in this field. If you leave this field empty, the system won't forward the e-mail.
Delete: If the received message has not been deleted by any plugin, should the system delete the message. If you select "No", the e-mail will stay in the mailbox until you manually delete it. This option should be turned OFFÂ and you should rather use the "forward" or the "save message" capability.
Delete Emails: Upon processing the mailbox, should the system delete the message or email from your external mailbox. If you select "No", the e-mails will stay in the external mailbox until you manually delete it. If you select "Yes" the emails will be automatically removed from your external mailbox. This option should be turn "ON" inorder not to retrieve the same messages everytime and to retrieve the next batch of messages from your external mailbox specially when you have messages more than the preference you specify.

If you are not sure of your server mailbox connection, please verify this with your hosting provider.

Step 2 Activate the bounce-back widgets for jNews

• From the mailbox page, click "Widgets (0)" under Assign columns next to your created Mailbox
• You need to enable the following with correct ordering:

1. Dictionary Filter
2. Newsletter Bounce

Step 3 Setup jNews Bounce Preferences

• From the Widgets page from step 2, click the "gear" icon under Preferences column next to Newsletter Bounce

Conditions

Number of Bounce: Specify the minimum number of bounced back e-mails the system should receive before executing the following actions.
If you specify 0, the subscriber will never be deleted, unsubscribed or unconfirmed.

Minimum Delay: Specify the minimum delay (in days) between the first received bounced back message and the latest received bounced back message.
Example
If you specify 3 (which means 3 days), the system will only execute the following actions if there are minimum X bounced back messages received and the elapsed time between the first received bounced back and the latest one is minimum 3 days.

Actions

Subscribe the user: You can subscribe the user to one Newsletter list
Unsubscribe the user: Do you want the system to unsubscribe the user from all Acajoom lists
Unconfirm the subscriber: Specify if you want the system to unconfirm the subscriber.
Acajoom won't send e-mails to an unconfirmed subscriber.
Blacklist the subscriber: If you select Yes, the user will be blacklisted.
Acajoom does not send any e-mail to a blacklisted user.
Delete the subscriber: Do you want the system to delete the Acajoom Subscriber. If you select "No", the user will always stay in jNews. If you select "Yes", the user will be deleted from jNews so he will be also unsubscribed from all your lists.

Delete message: Once the system identified the message as a bounced back, should the system delete the message. If you don't delete the message, the system may handle it twice so this option should be turn OFF only on debug mode.

Step 4 Verify the connection

• Once you created your mailbox, try to click Process or Connect to test the connection.
• If connection is not working, try to create a test Gmail account and test using Gmail credentials if that is working for you.

Step 5 Activate scheduled task and cron

• Verify if you have Task running to trigger your mailbox.
• Navigate to jTickets >> Tools >> Schedule and locate for Handle Messages
• Try to click Process button to test the connection.

For automation, please make sure you have a cron task setup. Please refer to article "Cron job setup".