Office 365 and sending e-mails from Sage 300 AR

Client just upgraded to Sage 300 version 2016 and Office 365.  They send invoices from AR (they don't have PrintBoss) and are getting the annoying message "a program is trying to send a message on their behalf...." where they have to click Allow for each invoice.  The client has used the program Click Yes in the past but it does not work with 64-bit version of Outlook.  Is there any other way to get past this message without implementing PrintBoss?