Hi, we currently have a client running both Exchange 2010 and Exchange 2016 in coexistence.
Does anyone have best practices for managing mailbox permissions during the transition phase? Right now you can technically manage mailbox rights using the old Exchange 2010 Management Console or use the ECP webpage that's in Exchange 2016.
Are there any up- or downsides to setting Full Access and Send As permissions using one or the other? Or will you only be able to set them in one place or the other depending on where the usermailbox is hosted? I would assume it's best to perform all changes on the new ECP once that server is active in the network.
