Read Without Email Verification (RWEV) is an option available to Business Premium users using the Outlook Add-in which allows a sender to send a secure message that an unregistered recipient can read just by answering the challenge question. In other words, they do not have to confirm they are the owner of the email address by entering a verification code. The option is offered on the challenge screen and needs to be unticked in order to send using RWEV.
Whilst this makes the process easier the risk of the email being read by the wrong person increases. It’s therefore key, if you choose to use Read Without Email Verification , that the challenge question/answer is known only to you and your recipient.
If you don’t have this option, then it hasn’t been enabled by your Mailock administrator.