User A and B are secretaries of Manager C and have permissions to send “on Behalf of” their Manager

User A works under User B and User B have access to specfic folders ( not full ) of User A

User A drafts an email and puts it in her Draft Folder

User B checks this email , modifies where required , and sends on Behalf of Manager C from User A’s Drafts

When the email is sent ( with Manager C in from field ) , instead of sending on Behalf of Manager C , it actually comes dierect from User B

When User B composes a new message ( with Manager C in from field ) it works.

For this to work , User B actually needs Full Access Permissions to User A’s mailbox ( not just to specific folders )