Problem with M84 window disappeared

[acca]

Hello,
I have a strange problem running M84 software on windows 10
Yesterday, i have accidentally double clicked the upper bar of M84 software. The window disappeared but it's icon is still present in the taskbar.
I tried the following without succes :
- maximise the window (from taskmanager)
- Alt tab
- Win + UP
- click the icon on the taskbar
- disintalling, cleaning the registry, reboot, reinstalling

I have made no change on windows before the problem occurs.

Does anyone already have had this problem please ?
Thanks