Questions about encrypting messages using Outlook 365 Message Encryprtion?‎

Frequent Contributor

I have a couple of questions about using message encryption in Microsoft 365, when using the Windows Outlook 365 client.

1. What form of encryption does Microsoft apply when encrypting an email? Is the level of encryption configurable if I want a higher level of encryption complexity?

2. What is required in order to send a fully encrypted email, securely to an email recipient who isn't within the Microsoft messaging ecosystem (i.e. Gmail, Yahoo Mail, etc.)?

2 Replies
best response confirmed by OneTechBeyond (Frequent Contributor)

Hi, there are full details in the link below, for Office 365 Message Encryption, it supports RSA 2048 for signature and encryption, and SHA-256 for hash in the signature.  This is not configurable as I understand it but there is the Office 365 Advanced Message Encryption add-on for customers looking for more overall control.


The second point, you can use Office 365 Message Encryption to send protected emails to consumer email services:


With Office 365 Message Encryption, your organization can send and receive encrypted email messages between people inside and outside your organization. Office 365 Message Encryption works with, Yahoo!, Gmail, and other email services. Email message encryption helps ensure that only intended recipients can view message content.


The requirements, which licences this works with and other questions are answered here.


Hope some of that helps.

Thanks, @Cian Allner!


This completely answers my questions!