You should encrypt email messages if you need to safeguard the privacy of the recipient. Using Outlook to encrypt an email message implies that the message is transformed from readable plain text to scrambled ciphertext. Only the recipient who possesses the private key that corresponds to the public key that was used to encrypt the message will be able to decipher and read the message. Anyone who does not have access to the appropriate private key, on the other hand, will see indecipherable content. Outlook provides two different encryption options:
S/MIME encryption – To use S/MIME encryption, both the sender and the recipient must be using a mail application that adheres to the S/MIME specification. Outlook is compatible with the S/MIME standard.
To use Microsoft 365 Message Encryption (also known as Information Rights Management), the sender must have Microsoft 365 Message Encryption installed on their computer, which is included in the Office 365 Enterprise E3 subscription.
New Encrypt button and updates to email encryption
Improved email encryption in Outlook has been made possible thanks to the latest Office release.
This is a feature that is only available to subscribers. Customers who subscribe to Microsoft 365 for Windows desktop clients will be able to use this service.
The Permissions button allows you to grant or deny permissions. Instead of the Permissions button, there is now an Encrypt button instead.
The new Encrypt button includes both encryption choices (S/MIME and IRM) in one convenient location. When using Outlook, you can only see the S/MIME option if you have a S/MIME certificate configured in Outlook.
Check out Encrypting with S/MIME or Encrypt with Microsoft 365 Message Encryption for further in-depth instructions on how to implement encryption.
Encrypting with S/MIME
S/MIME Encryption in Microsoft Office 2010
To begin this operation, you must first have added a certificate to the keychain on your computer’s operating system. Following the installation of your signing certificate(s) on your computer, you’ll need to set up them in Microsoft Outlook.
Options > Trust Center > Trust Center Settings can be found under the File drop-down menu.
Select Email Security from the drop-down menu on the left.
Select the S/MIME certificate from the Certificates and Algorithms section by clicking Choose and selecting it.
If you are an Office Insider with a Microsoft 365 subscription, here is what you can expect to see in the next months:
Options > Encrypt > Encrypt with S/MIME > Select Encrypt with S/MIME from the drop-down menu in an email message
If you have a S/MIME certificate installed on your computer, you’ll see the Encrypt using the S/MIME option appear.
For Microsoft Outlook 2019 and Microsoft Outlook 2016,
Select Permissions from the Options drop-down menu in an email message.
Encrypt with Microsoft 365 Message Encryption
Finally, select Send after you have finished writing your email.
Encrypt your messages with Microsoft 365 Message Encryption.
If you are a Microsoft 365 customer, this is what you should know about the new features:
Choose Options from within an email message, then Encrypt. Select the encryption type that includes the limits you wish to implement, such as Encrypt-Only or Do Not Forward from the drop-down menu.
Encrypt a single message
Please keep in mind that Microsoft 365 Message Encryption is included with the Office 365 Enterprise E3 subscription. Additionally, the Encrypt-Only function (the option under the Encrypt button) is only available to subscribers (Microsoft 365 Apps for corporate users) who are also using Exchange Online, as opposed to other subscribers.
Forecasts for the years 2019 and 2016 are included.
Select Options > Permissions from within an email message, and then select the encryption option that includes the limits you want to implement, such as Do Not Forward and click OK.
Encrypt only one communication at a time.
Select File > Properties from within the message that you are now typing.
Select the Encrypt message contents and attachments check box under Security Settings after clicking on the Security Settings button.
After you’ve finished writing your message, click Send.
Encrypt all outgoing messages
All outgoing messages are encrypted by default when you opt to encrypt them all. You can create and send messages just like you would with any other type of message, but all prospective receivers must have your digital ID to decode or access your messages.
Then, under the File tab, select Options >Trust Center > Trust Center Settings from the drop-down menu.
Select the Encrypt contents and attachments for the outgoing messages check box on the Email Security tab, which can be found under Encrypted email on the Email Security tab.
To make other changes, such as selecting a specific certificate to use, select Settings from the drop-down menu.