How Do I Grant Full Access to an Office 365 mailbox without it also loading into Outlook?

Question

As the SysAdmin, I sometimes need to grant myself access to someone's mailbox in Office 365. It's usually a temporary thing, just to accomplish a task or two, but sometimes it's somewhat long term.

When I do this, the mailbox automatically downloads into my Outlook client as well. I don't need it in my Outlook client as I can accomplish my tasks in the Outlook Web App by using a new tab or browser window.

When it downloads into my Outlook client, it takes up a bunch of space on my computer and it also takes longer to update everything when I start Outlook in the mornings. Also, I don't need the extra mailboxes in Outlook.

I'd like to have the permission I need without the entire mailbox downloading into Outlook. Is this possible?

Thanks, Jono

Answer 1

Yup - you just need to disable AutoMapping on the mailbox. But, it's not as easy as flipping a switch. You need to remove the current permissions and then re-add it with the automapping property to off.

So, if your account is the admin account and you need to have access to sharedmailbox you need to execute this (you must connect to Exchange Online Power Shell first):

Remove-MailboxPermission -Identity [e-mail] -User [e-mail] -AccessRights FullAccess

Add-MailboxPermission -Identity [e-mail] -User [e-mail] -AccessRights FullAccess -AutoMapping:$false

Note:

You can also change your outlook settings so shared mailbox is not downloaded. It's under your account settings --> Advanced settings.