There are two ways to have a Microsoft Office 365 integration: through the COM/VSTO add-in or an Office Add-in. What does it mean to have a Microsoft Office 365 integration? But you might want to think about it more if your current email management system is bogging down or crashing Outlook isn’t available on Outlook web, Mac, or mobile or requires a lot of IT help to set up and get running. How often do you think about how your email management system integrates with Outlook? Probably not very often, if ever.