Mailock for Outlook is an email encryption add-in for Microsoft Outlook (Windows) that enables users to send and receive encrypted emails directly from their Outlook inbox. Users compose messages as normal and toggle encryption on before sending. The add-in integrates into the Outlook ribbon, allowing one-click secure email composition without changing the standard email workflow. Key capabilities include: - End-to-end AES-256 encryption for messages and attachments - Recipient authentication via SMS one-time codes, Q&A challenges, or Unipass ID (an identity standard used in the UK financial services sector) - Sensitive data alerts triggered by predefined keywords, prompting users to encrypt before sending - Message tracking to see when a secure email has been opened - Message revocation, allowing senders to remove recipient access at any time — even after the email has been opened - Secure replies, ensuring the full conversation remains protected whether recipients use Outlook, Gmail, or other email clients The product is positioned for regulated industries such as financial services, where data protection and compliance are requirements. It is offered under both free and paid (Pro) plans. The paid tier includes additional controls suited for professional and team use.