MailChimp categorizes your campaign's bounces into 3 types:
- Syntax: A syntax bounce means the email address was entered incorrectly. Check for common typos, like "myemail@aolcom". You might be able to repair them.
- Soft Bounce: Soft bounces basically mean the email was sent to the server, processed, but for some reason was returned to us. Common reasons include: "user over quota," and "server temporarily unavailable."
****NOTE: If you're receiving an email returned into your own email account noting that someone is on vacation or is out of the office, that address is not necessarily getting noted as a soft bounce in MailChimp. Most of your recipients' servers should be set up to NOT report to us that the address bounced. If they did, your recipient might want to let their IT group know that they are getting taken off important mailing lists while they are on vacation. - Hard Bounce: A hard bounce basically means we sent your email, and the recipient's server outright rejected it. Common reasons include: "Account does not exist," and "domain does not exist."
MailChimp Cleans Your Lists Automatically
We'll clean bounce backs from your list automatically. You won't have to do a thing. Hard bounces are removed immediately. If a soft bounce is noted for a single campaign, we have attempted to send the email at regular intervals for up to 3 days. (We do what we can to help it try to get through, but we don't want you to look like an automated spambot either, so this helps keep a healthy balance.) If we get a soft bounce reported, we will record that as 1 bounce. After 7 of these soft bounce reports, 15 if there is a previous activity score, we'll clean that subscriber from your list. If you have an outside database that you need to update as well, download the bounced emails from your list and use them to clean your database. This can be done by navigating to the Lists page, click the View drop down and select Subscribers. On this page choose "cleaned" from the drop down box and then click the Download link.