Office 365 Integration Guide: Introduction

This guide explains how to integrate the CipherMail Email Encryption Gateway with Office 365.


  • A functional CipherMail Email Encryption Gateway (enterprise edition) or Webmail Messenger.

  • The CipherMail appliance should allow incoming email on port 25.

  • The CipherMail appliance should be allowed to send email on port 25.

  • The CipherMail appliance should have a static external IP address.

  • The CipherMail appliance is configured with a trusted TLS certificate (for using the built-in Let’s Encrypt module).

  • Office 365 account with exchange admin access.


Most cloud based providers like for example Azure or Digital Ocean by default do not allow outgoing email on port 25. Contact the cloud provider to lift these restrictions.

CipherMail Email Encryption Gateway Office 365


Microsoft recently locked down access to the incoming connector. By default you are no longer allowed to enable an incoming connector which is used to send email to external recipients. If you try to enable the connector, the following error message will be shown:

‘’’ Error executing request. For this service offering, you can’t enable an inbound connector. Please contact Support to enable it. Organization ‘…’, Service Offering: ‘O365_BUSINESS_ESSENTIALS’. ‘’’

Failed to update connector

Unfortunately only Microsoft can lift this block. Please contact Microsoft support to allow the incoming connector to be enabled.

If Microsoft is not willing to enable the connector, you should use some other relay option like for Example Amazon SES. Please contact us if you need help setting up Amazon SES with the CipherMail Appliances.