When deleting from personal Backup, the message is not deleted from global Backup. All operations with the message remain available in global Backup.
The group mailbox message is deleted from personal Backup of all users that have access to that group mailbox.
You can delete messages from Backup one at a time, as a group, or all displayed messages at the same time.
In personal user mode, you can delete your own messages and group mailbox messages from your personal Backup if your administrator has enabled this option in personal Backup settings.
To delete a single message from the global or personal Backup:
The message is deleted from Backup.