How to send encrypted email in Office 365 and the Outlook desktop client on Windows and Mac

This document shows how to send an encrypted email with your Lesley email account.  Recipients can be inside or outside Lesley University. 

Sending encrypted emails - Office 365

Sending encrypted emails - Outlook desktop on your Windows computer

Sending encrypted emails - Outlook desktop on your Mac

Receiving encrypted emails

Sending encrypted email through Office 365

1. Log into web mail at http://www.lesley.edu/office365. 

2. Click the Mail app to access your email. 

3. Click New or New message (depending on the version of Office 365 you're viewing) to start a new email. 

4. On the new email, click Protect (old version of Office 365) or Encrypt (new version of Office 365) to add encryption.  

Current Office 365:

New Office 365:

5. Fill in the To, Subject, and message body fields as normal and click Send.

Sending encrypted email through the Outlook desktop client on a Windows computer

In order to use the encryption feature, you must have the current Office 365 version of Outlook installed.

1. Choose New Email.

2. Click on Options.

3. Click on the Encrypt button.

4. Fill in the To, Subject, and message body fields as normal and click Send.

Sending encrypted email through the Outlook desktop client on a Mac computer

In order to use the encryption feature, you must have the current Office 365 version of Outlook installed.

1. Press the New Email button.

2. Press the Options button.

3. Press the Encrypt button, then press the Message button to get back to the window that allows you to send the email.

4. Fill in the To, Subject, and message body fields as normal and click Send. 

Receiving Encrypted Email 

Here’s what the recipient will receive depending on which type of email client they use. 

• On-campus Lesley people using Outlook on MAC or PC will see a red stop sign symbol in front of the email to indicate it is encrypted. When they click on the email link, they will see a message that they must authenticate their credentials. They will enter their email address and password.

• People accessing their Lesley email using a web browser, on or off campus, will see a lock symbol next to the email. 

• Non-Lesley email addresses will receive a message prompting them to click a Read the message button within the email.  This will bring them to a web page where they will log in with a one-time passcode which will also be sent to their email address. 

• After entering the passcode and clicking Continue, they’ll be presented with the contents of the email.  They can also download any attachments that were on the email. 

If they click the Reply button, their reply message back to the original Lesley sender will be encrypted.