The COM server can be registered by running MesysCOM(64).exe with parameter -regserver as administrator. This has to be done once. For unregistering the parameter -unregserver can be used.
In the installation directory two batch files RegisterMesysCOM and UnRegisterMesysCOM are provided so that the registration can be done without a command window. They can be started as Administrator using the right mouse button. This does not work in case the installation is on a network share, in case of a network a command window has to be used.