I need to give a couple of users ReadPermissions to some mailboxes. And I need the read-only mailboxes to appear in the users' Outlook via auto-mapping.
I know that you can achieve this via the mxExchDelegateListLink attribute in the Active Directory. However, this is not working with Office 365 and DirSync.
I figured out, that you can view the property in PowerShell using the following command:
(Get-MailboxPermission <mailbox> -ReadFromDomainController).DelegateListLink
It lists all the users whose Outlook will automatically map the queried mailbox.
How can I add users to that attribute via PowerShell? This Property is the same for each MailboxPermission object, so you probably cannot just edit the Property by itself.