On May 21, Microsoft officially released a major update of their operating system Windows 10 May 2019 Update (Version 1903). This update affects configurations and encryption keys similar to the installation of a new Windows operating system.
In order to protect Market products, the MetaTrader platform
binds all data to the operating system and hardware of the computer, on
which it is installed. Unfortunately, the update will make the launch of
installed and activated Market
applications impossible. Such applications will require a new
activation, because all products are bound to an operating system. We
have provided an additional activation for all products purchased from
the Market regardless of the operating system, just like we provided
activations after the previous release of Windows 10 October 2018 Update (version 1809).
Thus, MetaTrader Market users will not lose product activations
after the installation of Windows 10 May 2019 Update (version 1903).
Activations of demo products will also be lost, you will need to
re-download such applications from the Market.