If you’ve received a secure message, clicked on ‘Read my message’ and are taken to a screen like the one below then you will need to confirm your identity before you can see your message. This is done by answering a unique security question, set by the sender, which can only be answered correctly by you. The answer may be personal to you or shared over the phone or by text. Anyone else who has intercepted your email wouldn’t know the answer and so couldn’t read your message.
If you would like to reply securely to the sender click on the ‘Reply’ button at the top right of the screen.
If you don't know the answer to the challenge question take a look in the original email you received for the sender’s details and get in touch with them to check.