Hi,
I am evaluating; I have Office 365 shared mailboxes and those mailboxes have delegated access to me (and others). I.e. “I have full mailbox permissions” on the shared folder
I am able to add them to emClient by going to Tools|Accounts and selecting my Office 365 account.
Go to Exchange Web Services Tab. Under Delegation click on “show” next to accounts you can access.
On the pop up, Click Add, another pop up, enter the username of the mailbox (just like in Outlook) and hit search, it will find the mailbox, you click Add, it goes on the list.
Repeat as needed and then hit OK.
Jerry