Information
This policy setting can prohibit items from being permanently deleted until the database has been backed up.
Rationale:
To ensure that accidentally deleted items can be recovered, they should not be permanently deleted until the database is backed up.
Impact:
Additional storage space will be required until any pending items are permanently deleted.
If using a 3rd party backup solution that does not set the backup parameters on the Mailbox database as it is backed up then this setting should be skipped. Native backup solutions will update the database bits properly, allowing for the RetainDeletedItemsUntilBackup parameter work as intended.
Failure to evaluate the organization's backup solution in conjunction with this setting will result in increased database growth. To see the backup parameters mentioned above run Get-MailboxDatabase | fl *backup*
Solution
To implement the recommended state, execute the following PowerShell cmdlet:
Set-MailboxDatabase 'Mailbox Database' -RetainDeletedItemsUntilBackup $true
OR
Perform the following actions:
Launch the EAC (Exchange Administrative Center).
Go to 'Servers' on the left and click on the 'Databases' tab.
Double-click the database and go to the 'Limits' settings.
Ensure the Don't permanently delete items until the database is backed up box is checked and click Save.
Default Value:
False