(Optional) Send a test HTML message and improve, if needed.
If you would like access to more marketing email features (i.e., click rate, email editor design), you may want to consider using Eloqua instead. The tips below are intended for casual, informal emails such as interdepartmental newsletters, announcements, etc. However, the email client does offer the option to insert HTML code into the message body and render the code into visual content that can be emailed to your Office 365 Group or Google Group. The Outlook email client does not natively provide the option to create HTML emails.
