Bounce Classification Codes

March 26, 2020 Contributors

The bounce classification codes are identical for all versions of Momentum. Find below a list of these codes and their meanings.

Code Description
1 The response text could not be identified. (Undetermined)
10 The recipient is invalid. (Invalid Recipient)
20 The message soft bounced. (Soft Bounce)
21 The message bounced due to a DNS failure. (DNS Failure)
22 The message bounced due to the remote mailbox being over quota. (Mailbox Full)
23 The message bounced because it was too large for the recipient. (Too Large)
24 The message timed out. (Timeout)
25 The message was failed by Momentum’s configured policies. (Admin Failure)
30 No recipient could be determined for the message. (Generic Bounce: No RCPT)
40 The message failed for unspecified reasons. (Generic Bounce)
50 The message was blocked by the receiver. (Mail Block)
51 The message was blocked by the receiver as coming from a known spam source. (Spam Block)
52 The message was blocked by the receiver as spam (Spam Content)
53 The message was blocked by the receiver because it contained an attachment (Prohibited Attachment)
54 The message was blocked by the receiver because relaying is not allowed. (Relay Denied)
60 The message is an auto-reply/vacation mail. (Auto-Reply)
70 Message transmission has been temporarily delayed. (Transient Failure)
80 The message is a subscribe request. (Subscribe)
90 The message is an unsubscribe request. (Unsubscribe)
100 The message is a challenge-response probe. (Challenge-Response)