HES/HES - Inbound Filtering can only deliver mails for a managed domain to an IP address or an FQDN. If the receiving mail server becomes unavailable, HES/HES - Inbound Filtering will store the emails and will keep on retrying to send them for five (5) days on version 1.x and ten (10) days on version 2.0 before bouncing them back to the sender.
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Setting Hosted Email Security (HES) to temporarily deliver all mails for a managed domain to an email address
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