Select the public folders as described below, and then specify other settings of the protection plan as appropriate.
Note Public folders consume licenses from your backup quota for Office 365 seats.
To select Exchange Online public folders
Click Microsoft Office 365.
If multiple Office 365 organizations were added to the Cyber Protection service, expand the organization whose data you want to back up. Otherwise, skip this step.
Expand the Public folders node, and then select All public folders.
Do one of the following:
To back up all public folders (including public folders that will be created in the future), click Group backup.
To back up individual public folders, select the public folders that you want to back up, and then click Backup.
On the protection plan panel, ensure that the Office 365 mailboxes item is selected in What to back up.