Security and Email Security

How do I send a secure email in Outlook?

by Egress
Published on 21st Mar 2022

Sending an unsecured email can be likened to writing sensitive information on a sticky note and leaving it on someone else's desk: anybody can intercept and share that information. Fortunately, there are ways to ensure your emails are safe from the prying eyes of hackers through encryption, meaning your message — no matter how sensitive — is seen only by the intended recipient. 

An encrypted message is changed from plain text into ciphertext, which is unreadable and remains that way until it reaches its destination. That means that even the most determined hacker won't be able to gather sensitive information from the email. Once it arrives with the intended person(s), the encryption is removed, provided their identity has been confirmed.

Risks of unsecured email and benefits of encryption

Most of us are guilty of occasionally copying in the wrong person, clicking 'reply all' unintentionally, or misspelling an email address. Without the security of encryption, this can lead to serious problems. If an unauthorized person sees sensitive information not intended for their eyes, a mere accident turns into a data breach. 

There are significant risks associated with sending unsecured emails. These include:

  • Risk of attack
  • Data loss
  • Damage caused by data breaches
  • Breaking data protection regulations
  • Fines and legal action
  • Damage to business reputation

It's easy to become complacent about emails — something most of us have easy access to and use every day — but a simple layer of added security protects us from risk. Cybercriminals spend their lives searching for weak points they can take advantage of; the least we can do is make that more challenging for them. That's why it's so important to use all the tools at your disposal to make sure your emails are sent securely.

How to secure an email with Microsoft 365

For most Outlook users, emails are encrypted through S/MIME. This only works if both sender and recipient use Outlook and have their certificates installed, confirming their identities. That works well as a layer of basic protection against data loss.

Microsoft 365 also offers built-in message encryption for senders and recipients who use Outlook and have an Office 365 subscription. Here are step-by-step instructions outlining how to send an encrypted message when both parties use Microsoft 365. 

To summarize:

  • Use Outlook to open the email message
  • Navigate to the "File" and click "Properties"
  • Scroll to "Security Settings" and check the box next to "Encrypt message contents"
  • Compose your email message as you usually would
  • Click "Send"

However, if one party doesn't have the correct certificates or encryption tools, sending that email using plain text might seem the only option. Thankfully, Outlook add-ons allow users to encrypt every email they send — even if the recipient is outside the organization and using another email provider.

How intelligent email security can augment Microsoft 365's existing capabilities 

Intelligent email security tools, such as Egress Protect, ensure all outgoing emails are encrypted — even if they are intended for a recipient outside your network. Users can do this directly from Outlook with just a mouse click.

Another significant benefit of this add-on service is that emails are encrypted at rest, not just when they're in transit, meaning your data is protected at every stage. That minimizes the chances attackers have to access sensitive information, leading to a data breach.

Egress Protect also offers maximum flexibility for users. In this bring-your-own-device world where so many individuals are working from their laptops, phones, and tablets, Egress Protect operates on the principle of flexible authentication. That means sensitive information always remains secure, no matter what device that's in use. On top of this, users can select their encryption level depending on the sensitivity of the sent data. They can also control the actions of the email's recipient, such as preventing them from copying or forwarding data.

To further this, machine learning tools, such as Egress Prevent can detect contextual errors that might lead to a data leak. For example, the tool analyzes user relationships to understand what should and shouldn't be sent. This tool helps prevent sensitive information from being sent to a mistyped email address or an external client being included in an email with an attachment meant for internal eyes only.

While Microsoft Outlook's built-in encryption functionality offers a solid layer of security options for users, for maximum protection, consider add-ons that further improve your email security. These are seamless additions, removing any complexity for the user and making encryption an integrated part of daily life.