Action: Orgs with Inbound Firewall and/or MailServer Rules
***Immediate Action Required****
To avoid potential email delivery issues we recommend that you ensure that your customers' firewall rules are up-to-date. Please ensure that all the IP ranges below are added to their firewalls as they may be used at any time.
If the firewall does not support /19 CIDR ranges, this range will need to be entered as 32 separate /24 ranges: 22.214.171.124/24, 126.96.36.199/24 . . . 188.8.131.52/24.
In addition, please make sure that all of these address ranges are included in any delivery restrictions in their mail server configuration.
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