Assigning someone "delegate" access doesn't actually give them access to any folders (other than Inbox, Calendar, Tasks, Notes and Contacts) unless they are created after the delegate access is granted.

If I want someone to manage my "Sent" folder I need to give them explicit permission to this folder.  Same goes other folders - unless explicit permissions are granted to each folder, my delegate gets no permissions.

If I create a folder after granting "delegate" access than the delegate can see this folder, and can still see it after delegate access is removed.  Looking at the permissions of said folder, you can not see that the delegate has access.

The only way to give access to everything is via the backend, via Exchange Admin Centre or Powershell, but the user can not see these permissions in Outlook - on the mailbox or folder level.

Has any one else run into this issue?

Microsoft support have advised that people don't use folders in email.

Hi,

I understand that we need to change the sharing permission on each subfolders or the Sent Items folder if we want someone to access these folders. Delegate access permissions can only be set on these folders: Calendar, Tasks, Inbox, Contacts, Notes, and Journal. However, this is the default behavior in Outlook.

Permissions are inherited on new folders (Permissions are inherited on new folders but not propagated to existing folders) but not propagated to existing folders. It means if you grant someone access to your folders, that person has access to all items in the folders except those marked private. However, items in sub-folders are not available to the delegate unless you change the sharing permissions on each sub-folder. New sub-folders inherit the folder access permissions of the parent folder.

Regards,

Steve Fan
TechNet Community Support