Closing Cubase after long time minimized or unused

I think I got this problem several times. If I let cubase minimized ( or maybe still open) and
try to close it the next day, only the project window will close.
The main window still is open. I cannot stop the program not even with the task manager.
If I try to restart the computer, the system hangs until I use the reset button.
You know this could end in a damaged file system!

My system:
Intel Core i7-5820K 6 * 3.3GHz
32GB Ram
64Bit on Windows 10

Hi,

Did your computer hybernate in the meen time?

No. All these kind of system features are switched off.
It was a problem in Windows 8 too. And now in Windows 10 and Cubase 9 it is still there.

You know, you can minimize the project windows, while the main window title is still there.
Two days ago I left my PC in this state. And Yesterday it was impossible to awake Cubase again.
The main titlebar was still there. I saw the thumbnail window while mouse hovering over the
traybar but it was impossible to launch the project again. I had to restart the PC.

Maybe it is not the same problem on your Mac?

I think it is a matter of Windows. If a program is unused for a longer period, then windows checks
for all the allocated objects. Then it tries to get back memory from the program.
Later if you want to reactivate the program something strange happens.

When I launched the task manager, I saw activity of 9% for Cubase but it was unable to get back its
window in a period of 5 minutes. So I resetted the PC.