I've been working through some issues here attempting to migrate away from the MultiPeer Connectivity following the guidance in here, Moving from Multipeer Connectivity to Network Framework, and implementing a home-grown solution using NWBrowser and NWListener and NWConnections. I feel like I am 95% of the way there, but am experiencing an issue where my connection attempts seem to fail about 50% of the time. If I have two nodes say, one a physical iPad, and one a simulator on my Mac. I can start them both up, and they are both discovered with Bounjour no problem. Sometimes the "connect" no problem. Othertimes however when I attempt to "connect" from one device to the other, I get failures. I'd say it's about 50/50 success - fail at this point. The "dialing" device state enters "preparing" but never progesses past that, and on the "receiving end" I see receive error: POSIXErrorCode(rawValue: 61): Connection refused I'm at my wits end here with this, everything else in my migration I think is done...just need some insights maybe on potential causes for that error...

We have an iPad application that utilizes Multipeer Connectivity to enable local communication between devices running a copy of our app. Until recently, we were able to test this functionality in the Xcode simulator without any issues. We could easily set up multiple simulators and have them all communicate with each other. However, recently, either due to an upgrade to Xcode or MacOS, this functionality ceased working in the simulator. Surprisingly, it still functions perfectly on physical devices. If we reboot the development computer and launch the simulator immediately after the reboot (without building and sending from Xcode, but running the existing code on the device), the issue resolves. However, the moment we generate a new build and send it to the simulator from Xcode, the multipeer functionality stops working again in the simulator. The simulators won’t reconnect until a reboot of the physical Mac hardware hosting the simulator. We’ve tried the usual troubleshooting steps, such as downgrading Xcode, deleting simulators and recreating them, cleaning the build folder, and deleting derived data, but unfortunately, none of these solutions have worked. The next step is to attempt to use a previous version of MacOS (15.3) and see if that helps, but I’d prefer to avoid this if possible. Does anyone have any obvious suggestions or troubleshooting steps that might help us identify the cause of this issue?