I am using the free version of the add-in and I grateful the Mike from Sperry has created this office 365 add-in. This add-in helps to ensure that the email being sent out is to the correct person by providing a second check via the prompt. There are lot more features available if you go for paid one which also provides for added automation and check . I have requested for support on certain issues which Mike has kindly helped out with during the initially launching of this product in my environment. The best bit is you don't need to install on individually or via the intune endpoint manager anymore . You can just publish it with Apps for Outlook and it will be added in for all the applicable users you set when you publish the add-in.