Mailock works with any modern web browser on any device. As long as your browser is up-to-date, there is a good chance you can use Mailock. We recommend keeping your browser updated for the best experience.
To use our Outlook add-in, you need the classic desktop version of Outlook for Windows (see how to check). This commonly comes with Microsoft 365 Business Standard subscriptions or higher tiers. Standalone copies like Office 2019 also work. Our add-in works with any actively supported version of classic Outlook on any supported version of Windows (see Microsoft's end of support documentation).
We highly recommend keeping both your Outlook installation and Windows version fully updated. Staying current not only helps our add-in work properly, but more importantly keeps your system secure and compliant with data protection standards. The ICO warns that running outdated software that handles personal data risks data breaches and hefty fines.
Along with security, updating our Outlook add-in means you get all of the latest features and improvements we are continually working on. So we encourage staying current with our add-in as well.