UPNP folders not shown in Windows

[mminga]

Dear Simon,
I use HiFi Cast and Bubble UPNP as control apps both work as expected.
In the past, I used Windows, when I want to copy music on my smartphone or on a stick. I could use the provided structure of minimserver to find fast music and copy a folder.
At other UPNP server it is working as you see in the attached screenshot above.
I don't know why it now not any longer works. I changed the port of minimserver to 9000 and back to default without success.
I tried to switch off the firewall at Windows, without success.