Hello! First post. New to snaps.
I'm going through the RPI3 Getting Started and after I "Press enter to configure" and after I set up my Wi-Fi access point and click "Done", it begins "Applying network config", stops at 66%, apparently loses wlan0 (it disappears from the screen), and reports "brcmf_cfg80211_reg_notifier: not a ISO3166 code".
The access point is running a fairly recent DD-WRT and it's been working well for Macs, iOS, Android, and various media devices.
I'm trying to connect it to a 2.4GHz mixed mode AP on channel 6. (I set it to channel 6 after some Googling on this problem suggested that might help. No joy.)
I also saw some comments concerning possible under-powering of the RPI3, but I'm using the same set-up I have otherwise, and I did also grab a second USB power block to try that, too.