Yammer is connected to email in several ways: Yammer alerts users to new activity in conversations they follow by email, and users can subscribe to groups in email and post to conversations and groups by email. To make this work smoothly in your organization:
Email admins are responsible for setting up email correctly.
Yammer admins can customize the logo in email messages Yammer sends, and can require verification before users can post to Yammer by email.
Users can choose the types of notifications they receive.
For information about when email notifications are sent, see Yammer email and push notifications.
Initial setup: Follow Office 365 email best practices
Follow the mail flow guidelines in Security best practices for Office 365. If these configurations are not in place, users may be required to take additional steps to verify every message sent to Yammer by email.
Note: These email setting changes must be done by your internal email administrator. Yammer admins and support can't help configure your mail systems.
When using Yammer through an email client, it is recommended that SPF and/or DKIM is configured within your email system. For instructions, see:
Email settings admins control
Admins control the following settings:
Email settings users control
Users control what email notifications they receive.
Users can go to Yammer settings > Edit settings > Notifications and select which notifications to receive.
For more information, see Yammer email and push notifications.