@KBHMedia  thanks, all downgrade and back to normal, well except having to pusade my partner that IOT is actually worht doing again!!!

@KLH3468 I just found this thread after having called Linksys about my 2x HS200's and my 1x HS220 mysteriously stop working when I upgraded to their mesh system.  They admitted that it was a known issue and could not get them to work for me after a 1-hour remote session.  But after going through this thread, I attempted the Guest Network and reset all the switches to map to that and now they work fine, even with the updated firmware.  Thought everyone would like to know you can update your router and still get your TP-Link items to work.

@Tony This is still a problem. I tried the guest network thing and about a day later I noticed that my HS-200 and HS-210 switches aren't connected anymore!

@EFollmer does your linking to the guest network still work?

@FloridaGirl 

Go with what worked with others users and downgrade the firmware. I am not sure if Linksys has released a new update but I would follow up with them.

@Tony @FloridaGirl 

Folks, read my post from last year. I have resolved this issue. I have a very very rare occasional issue but I believe those issues are possibly just normal glitches that we see with other electronic devices. Seriously I only see this maybe once or twice every few months. And best of all, it's never all of my devices it's usually only 1,2, or 3 devices.

i never did anything with my firmware whatsoever. Just try my method, it worked for me.

chad

@FloridaGirl Yes, still working for me on guest network with upgraded firmware.  But