Understanding Messaging Gateway Exported Good and Bad Senders List (AllowedBlockedList.txt)

Products

• Messaging Gateway

Issue/Introduction

When exporting the Good or Bad Senders List from Messaging Gateway (SMG), the resulting AllowedBlockedList.txt file contains various record types (IP addresses, domains, and email addresses) prefixed with two-letter codes. These codes are not explicitly explained within the exported file.

Environment

• Product: Messaging Gateway (SMG)
• Feature: Reputation > Senders (Good Senders / Bad Senders)

Cause

Messaging Gateway uses a shorthand prefix system to categorize different types of sender entries (connections vs. individual senders) and their respective actions (allow, reject, or third-party list membership) during the export/import process.

Resolution

When reviewing or preparing an AllowedBlockedList.txt file for import, use the following prefix definitions to identify the record type and intended action:

Prefix Definitions

 

 

Prefix	Meaning	Description
AC	Allowed Connection	The specific IP address or CIDR range is allowed to connect.
AS	Allowed Sender	The specific email address or domain is permitted to send mail.
RC	Rejected Connection	The specific IP address or CIDR range is blocked from connecting.
RS	Rejected Sender	The specific email address or domain is blocked from sending mail.
WL	3rd Party Allow List	The entry is associated with a configured third-party allow list.
BL	3rd Party Block List	The entry is associated with a configured third-party block list.

File Format Guidelines

• Each entry in the text file must follow the format: Prefix:Value (e.g., AC:192.0.2.1 or AS:example.com).
• The list includes both network-level identifiers (IPs) and application-level identifiers (domains/emails).
• Ensure there are no leading or trailing spaces around the colon or the prefix codes.