Rekordbox freezes after activation

As soon as I enter my activation number (Rekordbox DJ), the program freezes as it obviously tries to build up the new surface. However long I wait, it does not recover. When I force close it and open it again, the upper part of the pages stays white and the program is frozen again. This applies to all versions of Rekordbox I have. The only way to get Rekordbox back to work is to uninstall everything, complete re-installation and NOT ACTIVATING it.

Any help`?