Update:
The problem appears also with Binance. It also appears on my vps with windows server instead of windows 8 on a virtual environment on my mac. experimenting with uac etc doesn't help.

However the problem disappears when switching to an old version of Zorro, here 2.18, instead of the newly installed beta as of today.

So the problem isn't gone, please suggest anything that comes to your mind:)

Thx Thomas