Exchange Mailboxes must be retained until backups are complete.

Severity	Group ID	Group Title	Version	Rule ID	Date	STIG Version
medium	V-228376	SRG-APP-000231	EX16-MB-000270	SV-228376r879642_rule	2023-12-18	2

Description
Backup and recovery procedures are an important part of overall system availability and integrity. Complete backups reduce the chance of accidental deletion of important information and make it possible to have complete recoveries. It is not uncommon for users to receive and delete messages in the scope of a single backup cycle. This setting ensures at least one backup has been run on the mailbox store before the message physically disappears. By enabling this setting, all messages written to recipients who have accounts on this store will reside in backups even if they have been deleted by the user before the backup has run.

Description

Backup and recovery procedures are an important part of overall system availability and integrity. Complete backups reduce the chance of accidental deletion of important information and make it possible to have complete recoveries. It is not uncommon for users to receive and delete messages in the scope of a single backup cycle. This setting ensures at least one backup has been run on the mailbox store before the message physically disappears. By enabling this setting, all messages written to recipients who have accounts on this store will reside in backups even if they have been deleted by the user before the backup has run.

ℹ️ Check
Open the Exchange Management Shell and enter the following command: Get-MailboxDatabase\| Select Name, Identity, RetainDeletedItemsUntilBackup If the value of "RetainDeletedItemsUntilBackup" is not set to "True", this is a finding.

✔️ Fix
Open the Exchange Management Shell and enter the following command: Set-MailboxDatabase -Identity <'IdentityName'> -RetainDeletedItemsUntilBackup $true Note: The <IdentityName> value must be in single quotes.