Microsoft Outlook is a prominent email client used for sharing crucial information amongst organizations. This information passes over the internet and contains some confidential details. These details are subject to being hijacked by cybercriminals. Therefore, it is necessary to maintain the confidentiality of your email data. In this context, many users want the solution of how to send a secure email in Outlook. This article explains the two encryption methods that allow you to send a secure email in Outlook. 

Encrypting the email in Outlook converts the message into a scrambled ciphertext. Only the recipient having the private key can interpret the message for reading. Following are the two ways to encrypt email in Outlook.

1. S/MIME Encryption
2. Microsoft 365 Message Encryption (OME) 

Before explaining these techniques in detail, let's go through some benefits of Outlook email encryption.  

Why Do We Need To Send an Encrypted Email in Outlook?

Generally, encryption adds an essential layer of security. It ensures that your message is read by the supposed recipient. Following are some additional benefits that increase the demand to send a password-protected email in Outlrtantook. 

1. Outlook email encryption uses integral aspects, including Confidentiality, Integrity, and Authentication. It ensures that the classified information remains to abscond from unauthorized individuals. 
2. Encrypting email in Outlook saves additional costs in setting up the parallel encryption server. 
3. It can also save the inconvenience of getting additional programs for email security. It results in accelerating the organizational process, which leads to higher efficiency.

After discussing the benefits of sending password-protected emails in Outlook, let’s move on to how to send a secure email in Outlook. 

How to Send an Encrypted Email in Outlook

We have already stated that there are two effective methods to send a secure email in Outlook. Here we are providing the detailed procedure to perform these encryption techniques.

Method 1 - Encrypting With S/MIME Technique

S/MIME stands for Secure/Multipurpose Internet Mail Extensions. This encryption technique works on the mail application that supports the S/MIME standard. Both sender and receiver must have installed the S/MIME supported email client. 

Before starting this process, you must have set up the signing certificate on your computer. After that, configure it with your MS Outlook by following the steps discussed here.

Step 1: Purchase Digital IDs or Certificates

• Click on the File menu and select the Options tab. 
• Now, go to the Trust Center and click on the Trust Center Settings.
• Select the Email Security from the left pane. 
• Then, click on the Settings option under the Encrypted email. 
• Now, select the Get Digital ID to purchase a new certificate. 

Step 2: Import a Digital ID

• After selecting Email Security, click on the Import/Export under the Digital IDs (Certificates) panel.
• Then, choose the Browse option to Import Existing Digital ID from a file. Provide the password and click on the Ok button.  
• Here, you can set the Security Level of the password. After providing this press Ok to import a digital certificate.

These two steps explained how to import a Digital ID (certificate) into MS Outlook. After this, you need to send an encrypted email in Outlook using your Digital ID (Certificate). It will help your contacts to add you and the associated ID to receive the encrypted email. 

Step 3: Send a Digitally Signed Mail

• Open the Outlook account and click on the New Email to open a new mail wizard.
• Here, select the Options tab from the menu bar. Then, click on the Message Options.
• Choose the Security Settings from the Properties dialog box. 
• Check on the Add Digital Signature to this Message. You can also verify which certificate you are using from the Change Setting option. 
• Then tap on the Ok button to add digitally signed mail into the message. 
• In the end, compose a mail and include the Public Key and instructions. It will help the recipient to specify the encryption settings on their system. 

The above three steps will only help you to understand how to encrypt email in Outlook using S/MIME. Now, perform the last step to send a secure email in Outlook through this approach. 

Step 4: Send Password Protected Email in Outlook Via S/MIME Approach

You would require a Public Key to send an encrypted email to your contact. However, if you have the digitally signed certificate of your recipient, follow the instructions to send a secure email.

• Open the digitally signed email and Right Click on the Sender’s name.
• Now, Add or Update the sender to your contact list.
• Then, tap on the Certificate option from the Contact card. It shows the associated certificates. 
• After that, choose the New Email option.
• From the Options tab, hit on the Message Options button.
• Now, select the Security Settings option from the Properties dialog box. 
• Here check on the Encrypt message and tap on the Ok to proceed.
• Finally, you can Compose a new mail with attachments to Send to your recipient.

These four steps explained the entire process of how to send a secure email in Outlook via the S/MIME technique. Now, let’s move on to the other approach called Microsoft 365 Message Encryption (OME).

Method 2 - Encrypt Email Using Microsoft 365 Message Encryption Technique (OME)  

This approach doesn’t require installing any certificates. It provides the alternate solution of how to send a secure email in Outlook to any email recipient. However, you can only use this option if you have an Office 365 email account (Exchange Online). 

Apart from this, you must have the Outlook application installed as a part of a Microsoft 365 subscription. Unfortunately, the most popular Office 365 Business Essentials and Office 365 Business Premium plans do not include OME. You have to upgrade to the following:

• Office 365 Enterprise E3 or E5.
• Microsoft Enterprise E3 or E5.
• Office 365 A1, A3, or A5.
• Office 365 Government G3 or G5.

Alternatively, you can include the Azure Information Protection Plan 1 in your Office 365 subscription. However, most users find it more complex and expensive.

To Upgrade the Plan:

• Visit Office 365 official website and Sign In to your Office 365 administrator account.
• Now, click on the Admin option from the option tiles. 
• After that, from the left pane, tap on the Billing and select the Subscriptions under that.
• Here, click on the Switch Plans and upgrade to a higher plan.

Now, start composing a new mail to verify whether OME is available or not. You can send a secure email in Outlook with OME encryption if the Encrypt button is enabled (not grayed) in the top menu.

Sending Encrypted Emails Using Office 365 Message Encryption (OME)

• After Sign In, start composing a New Email.
• Click on the Options from the top menu. Then, select Encrypt.
• Now, you can see a message informing, “This message is encrypted. Recipients can’t remove encryption.” 
• After composing the message, click on the Send button to send it.

The recipient will have to perform some extra steps to access your encrypted email:

• They need to request a passcode that will be received in another email.
• After receiving the second mail, they need to copy the passcode and paste it into the encrypted email’s web page manually.

These two methods help to send an encrypted email in Outlook. Moreover, many users have backed up their Outlook email data in PST file format. This format allows them to protect the email data using a password. 

Final Verdict

We have discussed the two methods of how to send a secure email in Outlook. By using the digital certificate (S/MIME) and Microsoft Office 365 Message Encryption (OME) techniques, organizations are in good positions to protect the content and attachments sent via Outlook. Moreover, S/MIME is a trustworthy technique while communicating with a government agency or large enterprise as they already set up encryption certificates.