Microsoft 365 message encryption (OME)

With Microsoft 365 message encryption, you can send and receive encrypted email messages between people inside and outside your organization. Email message encryption helps ensure that only intended recipients can view message content. 

Sending an encrypted message 

Outlook on the desktop 

1. In Outlook, select New Email

2. From the Options menu, select Encrypt 
   
   
   
   

3. Selecting the arrow next to Encrypt will give you a few more options (Encrypt-only is the default setting):
   
   
   

Outlook on the web

1. In Outlook on the web, https://outlook.office.com/mail

2. Select New Message

3. Select Encrypt
   
   
   
   

4. A header will show in the composition window letting you know that this message is encrypted, and you have options to ‘Change permissions’ or ‘Remove encryption’.

5. Selecting Change permissions will give you a few more options (Encrypt is the default setting):
   
   

   Open

   

   
   
   
   

Receiving an encrypted message

Outlook with a Microsoft 365 account

Desktop/Browser:

• If you're using a Microsoft 365 email account in Outlook 2016 or Outlook on the web, you shouldn't have to do anything special to read your message.

• You will see a lock icon on the message and when you open it there will be a notice at the top of the message indicating that the message is encrypted.

Mobile app:

• If you have a Microsoft 365 account and you're using the Outlook mobile app, the message should just open.

To reply to an encrypted message

1. Choose Reply or Reply All

2. On the page that appears, type a reply and choose Send
   
   

Other email accounts or Outlook without a Microsoft 365 account

Users with other email accounts will be prompted to obtain a one-time passcode and read the message in a browser window.

1. Select Read the message

2. Select how you'd like to sign in to read the message. If your email provider is Google, Yahoo, or Microsoft, you can select Sign in with Google, Yahoo, or Microsoft respectively. Otherwise, select sign in with a one-time passcode.

3. Once you receive the passcode in an email message, make a note of the passcode, then return to the web page where you requested the passcode and enter the passcode, and select continue.