Introduction to cyber security: stay safe online
Introduction to cyber security: stay safe online

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2.2 Sending signed and encrypted email

Below is an optional activity.

Activity 1 Optional activities

Timing: Allow about

As an alternative to exchanging encrypted emails with a colleague or friends, if you have set up Mailvelope or another PGP email client you can send an encrypted email to an automated mail box at The Open University:

  • First send an email that simply says ‘public key’ to: [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)]
  • The server will send back an automatic reply that includes the current PGP public key for this mail box.
  • Again follow the instructions on the Mailvelope website, or for the PGP encryption software that you are using, use this public key to create a new email with a message ‘testing encrypted content’

    Note that you need all the characters including -----BEGIN PGP PUBLIC KEY BLOCK----- and -----END PGP PUBLIC KEY BLOCK-----

  • Send your email to: You will receive an email back from us to say that we’ve successfully decrypted your message! If you don’t receive an email within 2 hours, please try again.

To find out more about Mailvelope’s features or get help with specific problems visit Mailvelope help.

End-to-end encryption as a service

It can be a problem for organisations and individuals to set up the software for encrypted emails on all the devices that they use.

End-to-end encryption can be provided as a service. At the time of writing, ProtonMail and Tutanota both have a good reputation and also offer a free service.

Follow the instructions at or to set up two FREE accounts with the same service in two separate browsers. Then use these accounts to send a message from one account to the other.

In the last few sections you have explored what is involved in using cryptography to encrypt and sign email communications.

  • What seemed to be the hardest parts of the process?
  • What would you want to improve to make it easier?
  • How does the use of ProtonMail or Tutonota compare with the use of Mailvelope or other secure email software?

You may find it useful to compare your experience with the instructions for one of the other tools mentioned in Section 2, Putting cryptography to use.

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