It is important to note that the Outlook client is not necessarily connected to an Exchange server. It is also possible to connect, for example, a Gmail inbox via a POP3/IMAP account. For these accounts the Outlook add-in is not supported. Instead, you can use the Trustifi Chrome extension.
Requirements for the Outlook client:
Windows: Outlook 2013 or laterMac: Outlook 2016 or laterUser must have access to the add-in storeInstalling add-ins must be enabled by the administratorWindows: Internet Explorer 11 or Microsoft Edge (depending on the Windows and Office versions) must be installed but doesn’t have to be the default browser