I know this is an older thread, but I thought I would add my solution. We recently switched from Exchange 2010 on premise to Office 365 in the cloud. As a result our SMTP settings needed to change but could not get O365 to accept the SMTP settings in Machform. So here's the deal - you can get it work by configuring Machform to use the "direct send" method (Option 2 in this article: https://support.office.com/en-us/article/How-to-set-up-a-multifunction-device-or-application-to-send-email-using-Office-365-69f58e99-c550-4274-ad18-c805d654b4c4)
It requires that you have an Exchange connector set up to accept email from the public IP address where your machform is installed, and then you use the following value for the SMTP Settings (in Machform):
SMTP Server: domain-com.mail.protection.outlook.com
Use Authentication: No
Use TLS/SSL: No
SMTP Username: enter a valid O365 user account
SMTP Password: Leave blank
SMTP Port: 25
At least this is what eventually worked for us. Hope it helps someone!