Hello

I am trying to open some additional mailboxes when I use Outlook 2016 on my Macbook Air

I am using the latest version of OSX

Office is the latest patched version 2016

When I try to add the additional mailboxes in tools>accounts>advanced>delegates the button is greyed out.

What can I do to resolve this?

I have used this feature before without a problem.

I have been moved from Exchange on premise to Office 365 online but would this stop me opening the other mailboxes? They have all been moved and I have the permission to open them.

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