Unfortunatelly, it still doesn't work. When synchronizing by manually setting the IP, I have to change it every time when IP changes... that sucks.
Also, I have a much bigger problem:
After trying to get a connection by manually typing the android's IP, only the treeview of my internal memory is shown in BestSync. BUT I have large data to sync so I need access to my external sd card.
I tried lots of combinations. Each time I try to sync a folder from notebook to external sd, I get the error "success:0, failed:1"... Synchronizing the internal memory works just fine, but that is no option for me.
I think, the problem is that BestDAV Server has no rights to access external sd card data... How can I change this on my Android 7.0 (Nougat version) ?
If there is no way to solve this, I unfortunatelly have to cancel the order and need to try another sync software.