Fortnite launcher does not start is not displayed?

So with a buddy it is so that he starts the launcher and it appears at the bottom of the task bar but the window seems to be insecure there. He has already tried the following things:

Process finished restarted

antivirus identified

Checked if it is in another window

reinstalled

Updates and drivers reinstalled

Also right click on the symbol?

Yes then you can either solve it from the taskbar or maximize what it then again "invisible" appears.

Hold the mouse over the icon in the taskbar, so that the preview appears. Then Maximize on the preview window right click.