How to Send and Receive an Encrypted Message: Email Encryption in Office 365

By Danelle Van der Koon| October 29, 2020

As our digital lives become increasingly enmeshed with our work lives, there is a concern for businesses to make sure that information is not released unintentionally via malicious means or otherwise. In today’s digital workplace, it has become routine to rely on email and other applications to communicate sensitive information with colleagues and partners, including passwords, social security numbers, confidential terms and conditions, etc., but how can you make sure that your business’s data does not fall into the wrong hands?

One way is to use encrypted email messaging. This technology ensures that your messages and attachments can only be viewed by their intended recipient(s).

How to Set Up Encrypted Email in Office 365

In the Making Seamless Security Real with Microsoft 365 Demo, we look at how Office 365, Windows 10, and Enterprise Mobility + Security come together to enable workplace productivity while keeping your sensitive data secure. As part of this holistic approach to modern threat defense, message encryption by Microsoft Office 365 is easy for anyone to use. Follow these steps to get started!

How to Send an Encrypted Message

Once you’ve composed your email like normal, add your intended recipient and select Options --> Permission. Different protection options will appear allowing you to select the best one based on the contents of your message. Some of these options will already be pre-defined by your admin, however, you can always apply your own rule to the message. For example, a rule can require a message to be encrypted if it is sent outside of your organization.

encrypted email

How to Open an Encrypted Email?

If you’re on the receiving end of an encrypted message, here’s what you can expect. Usually, encrypted messages will feature the words [Secure] in the subject line to alert you that the message is confidential. The message text will also state that you have received an encrypted message.

secure email

To open the message, if you are a Microsoft 365 user, click the attachment and a new page will open in your web browser stating that you have received an encrypted message. If you are a non-Microsoft 365 user, you will need to click on the link in the body of the message.

encrypted message

There are two options available to view the message: Sign in or Use a one-time passcode. Sign in is used when you are the only user who will be receiving and viewing the message.

If you want to be able to send the message to others, you will want to select one-time passcode. The passcode will be sent to your email and will expire after 15 minutes. Once you receive your passcode, you can copy it and paste it into the encrypted message browser.

One-time passcode for encrypted email

After you select continue, you will be able to view the message and open any attachments.

To respond to an encrypted message, simply choose either reply or reply all directly on the encrypted email. A separate page will then appear where you can type your reply. When you are done, select send. A copy of the encrypted message will also be sent to you.

How to Set Up Message Encryption in Microsoft Office 365

If you want to forward or share an attachment from an encrypted message, it is important to select the correct sensitivity. This can be easily done after opening your attachment by using the Azure Information Protection Toolbar, which appears at the top of the attached document. This toolbar respects the policies your organization created for secure attachments/messages, and you can select a sensitivity option directly in the document. The 5 most basic options include Personal, Public, Internal, Confidential, and Secret.

azure information protection toolbar

Once you select the option appropriate for your message, you can save your attachment and encrypt it in a new message to send.

Next Steps

As you have learned, securing your data beyond your physical walls and laptops is important since unsecured messages and attachments can be compromised. Encrypting a message requires extra steps that you might not normally perform when sending an email or message, however, it only takes a few extra steps to help save you from a catastrophic data breach in the future.

There are many options available on Office 365; the main challenge is finding the option that is right for you. Want to learn how your business can better protect its data with encryption and which option is best for you? BDO Digital develops security programs for midmarket organizations and specializes in leveraging the security tools in Microsoft 365 to help keep you focused on keeping your users secure and productive.

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