[Rerun]

I have two Windows 10 machines running mobile sheets and want to sync them. If I run the device sync and set machine A to be the server and machine B to be the client, the app server is assigned to an IPv4 adress and both devices see each other. But if done otherway round and I set machine B to be the server and machine A the client the server is getting an IPv6 adress assigned and remains invisible to the other device.

Why are both machine behaving differently and why are the machines invisible to each other?

[Zubersoft]

This is a bug in my software. It is supposed to look at all of the available network interfaces and use the first IPv4 one. Unfortunately, for the library sync, it's only looking for the first network interface and using it regardless of whether it's IPv4 or IPv6. So it's just random chance that it worked for you on one device and not the other, because on one device the IPv4 adapter came first. I will get a fix in place ASAP. Thanks for making me aware of this issue.

Mike