I noticed this error today. I’m not sure what happened. I haven’t run the multi-protocol firmware and instead split Zigbee and Thread between a SkyConnect and the on-board radio in my Yellow.
I’m using the SkyConnect as my Zigbee radio, and haven’t updated the firmware.
I tried going through to Configure Zigbee, but when I get to the Serial Port Settings page and click Submit, it says “Failed to connect”.
Also I noticed on the Zigbee devices page, it says “Failed setup, will retry: The serial port is locked by another application”
I found some other posts about using the Add-On to flash the SkyConnect, but initially couldn’t figure out which add-on they were referencing.
I just found a thread that linked the Silicon Labs Flasher. Installed and ran it. Initially with ZHA still enabled, then a 2nd time with ZHA disabled. It seems to have helped the situation. Now it’s no longer saying “The serial port is locked by another application” which is good, but the Zigbee devices still aren’t working.
Oddly, under ZHA, it’s saying Yellow Multiprotocol still.
I do happen to have a Sonoff Zigbee 3.0 Plus dongle that I could try next.
Any other ideas? I’d like to keep using the SkyConnect since it worked so well until now.