@Brook Did the OP really accept this as a solution, or did you accept it for him? Many of us bought these devices BECAUSE they could be accessed locally. If you've fixed a security fix, you haven't...

@Brook "We were aware that there were some security vulnerabilities on the previous firmware of HS100/HS110, some third-party software such as home assistant might take advantage of the vulnerability...

Kasa searches locally for the switch but won't find it from the 5GHz side - the protocol doesn't flow across bands. Most often you can rename your 5GHz SSID (don't rename the 2.4GHz or the HS100...

Sounds like you might not be directly connecting to the switch but instead the app is trying to go through the TP Link cloud service. One reason is if your phone is on your 5GHz signal - it might...

@blimnimtharp I think the point was that if the HS210 doesn't work it's almost certainly wiring because they're seldom dead on arrival, and wiring 3 way switches is harder than wiring 2 way switches...

Grab an old phone, install a clock screen saver, plug it into a charging stand and leave it by the bed. Turn off the screen lock. Multiple duties as an alarm clock, nightlight, emergency phone (you...