All settings gone?!

I’ve been trying out Em Client 7 for a few days now, and was quite happy with it.
Yesterday I started the program using the shortcut I placed on the (Windows 10) taskbar (as I did before without issues), but to my surprise the program started up welcoming me as a new user. So it was like a fresh install. All my settings and accounts were gone.
I found out that - strangely enough -  I could start the program WITH all settings and account intact, if I used the shortcut in my system tray instead of the one on my taskbar. I even had 2 programs at the same time on my screen; the “fresh” one and the “old” properly working one.

Today I booted my pc and found out that that trick did not work anymore, and also the shortcut in my startmenu folder was missing now. So I have to start from scratch again, I guess, as I did not find a way to restore my settings.

I hope there’s a solution for this annoying problem. I was falling in love with EM client, but this is really weird and not very comforting in case I choose to keep using this software…