Allow S/MIME certificates without a matching email address.Allow only corporate mailboxes to be added.The following list shows the preferences that are covered in this article: These keys are CFPreferences-compatible, which means that it can be set by using enterprise management software for Mac, such as Jamf Pro. The following preferences can be used to simplify account setup for Microsoft 365 (or Office 365) mailboxes, help protect company data, and support a streamlined user experience. Force a particular preference, which users can’t change.Set a default preference, which users can change.Applies to: Outlook for Mac, Outlook LTSC for Mac 2021, Outlook 2019 for MacĪs an IT admin, you may want to provide Mac users in your organization with a standard set of preferences for Outlook in either of the following ways: