Bounce Messages

As you're probably aware bounced email is part and parcel of sending emails from incorrect spelling of a name in an email address to being rejected because of spam.

There are two main groups of email bounce messages the first, the 400s are deferral messages and the sending mail server will try to resend the message.  The second group, the 500s are permanent failures and the email will not be resent.

The 400 Group

A 400 bounce message usually means there has been an issuing in the transport of the email which can cause a delay.  Black Pearl Mail attempts to resend the email for up to 48 hours. Below are some of the common messages:

421 [GL01] Message from (X.X.X.X) temporarily deferred
450 The user you are trying to contact is receiving mail too quickly. Please resend your message at a later time. If the user is able to receive mail at that time, your message will be delivered.
451 Temporary local problem - please try later
452 Over Quota

The 500 Group

Below are some of the common messages from the 500 group:

Invalid Email Account

If you get error 550 (or 554, depending on the recipient’s email server), it means that the email address you are sending the message to does not exist.

Example of messages associated with this error:

550 [email] User unknown

550 Sorry, no mailbox here by that name. (#5.1.1)

550 Requested action not taken: mailbox unavailable

550 No Such User Here

550 Invalid recipient

5.1.0 – Unknown address error 550-‘MAILBOX NOT FOUND’

550-5.1.1 The email account that you tried to reach does not exist.

550 5.1.1 [e-mail]: Recipient address rejected: User unknown in relay recipient table

554 delivery error: This user doesn’t have a [name of the service] account

554 delivery error: Sorry your message to [email] cannot be delivered. This account has been disabled or discontinued

550 #5.1.0 Address rejected [email]

Mailbox Full

Mailbox full is usually associated with a 552 error message and can have the below text available:

Mailbox is full

Disk quota exceeded

User is over the quota. You can try again later.

The recipient’s mailbox is full and can’t accept messages now.

Mailbox limit exceeded while appending message

Requested mail action aborted: exceeded storage allocation

Black List

Although Black Pearl Mail actively monitors all its servers against over 100 spam lists and can remove the server affected within 10 minutes of being added, sometimes emails do get bounced due to the 10 minute time window.  The generic error for this is 550 and may have words such as blocked, spam list etc.

If you are unsure on a bounce message please forward it to and we can help.

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