Outlook Message Encryption

WVU Information Technology Services (ITS) provides Microsoft 365 Outlook email users with the ability to send and receive encrypted email. This is primarily intended for emails to parties outside of WVU who request additional encryption.

• Encrypted email messages can be sent to anyone, regardless of the recipient’s email address.

• Special certificates are not required, as the recipient’s email address acts as the public key.

• Subsequent email threads in each message are encrypted. 

• Recipients don’t need a Microsoft 365 account to view encrypted messages or to send encrypted replies.

• With an appropriate app (an OME viewer), encrypted messages can be viewed on mobile iOS and Android devices.

This form of encryption is appropriate for communicating confidential information through Microsoft 365. It is not, however, compatible with certificate-based encryption that an outside (i.e., non-Microsoft 365) party might use to communicate with you.

How to encrypt a message

A gateway based policy rule is used to recognize that you wish to encrypt an email message. To encrypt a message in Outlook, you must include the text string “[SECURE]” in the Subject line.  The square brackets and upper-case characters are required. 

Receiving an encrypted message

If you are in an Outlook client, you can view the message in one of two ways:

• Sign in with a Microsoft (Work or School) account

• Request and use a one-time passcode

Outside mail accounts, including MIX, as well as iOS and Android mobile devices work best by using the one-time passcode. The one-time passcode gets sent to the same email account to which the original encrypted message was sent. The one-time passcode will expire after 15 minutes from the time in which it was sent.  Copy or transcribe the eight-digit code into the one-time passcode box, and click the Continue link.

iOS and Android devices

If you have an iPhone, iPad or an Android device and you have received a message encrypted with Microsoft 365 Message Encryption, you can use the free OME View app to view the message and send an encrypted reply.

For iPhone or iPad OME Viewer download link and instructions, visit View encrypted messages on your iPhone or iPad.

For Android OME Viewer download link and instructions, visit View encrypted messages on your Android device.