@test-lab-user 

Hi, I’m experiencing exactly the same issue after the firmware update (1.4.x).

Local control via the API stopped working completely (handshake/403 or connection failures), even though the devices are still reachable on the network. I’ve tried all local approaches (kasa / PyP110 / direct LAN access), but nothing works anymore.
 

On a previous firmware update, I was able to resolve a similar issue by toggling the “third-party compatibility” option in the Tapo app, but this time it has no effect.

Firmware downgrade is not possible, so I’m currently stuck. My monitoring / metrics setup (10× P110 devices) has been broken since the update.

Did you ever find a working solution or workaround ?

Regards

I purchased 2x P110's about a week or two ago from Amazon. I set both up identically (both in the same double powerpoint), and all on the latest firmware, and same hardware version. In the app, everything looks identical. However, one has this issue and the other one is fine. Both work in the Tapo app, and both work via Matter setup in Home Assistant. But only one works via setup through TP-Link Smart Home integration. The one that doesn't work has handshaking failure. 

Both devices are using Firmware Version: 1.4.1 Build 251020 Rel.183216 - Hardware version 1.0

Hopefully a fix comes soon.

Cheers,

higgalls

  @test-lab-user 

you need to enable the 3rd Party option inside the Tapo App settings.

This will allow access for your script.

However, this only worked for me until version 1.4.0. 

From version 1.4.6 this stopped working for unknown reasons.

  @Stefan13 

That doesn't work for everyone. With third party extensions enabled, I have 2 idential plugs - one works and the other doesn't. All same firmware and hardware numbers. Bought exact same time. 

  @test-lab-user 

vaing the same issue with certain devices. Each is on 1.4.2, but the ones that have 1.4.4 rolled out, those seem to work. If anyone knows how to force push a firmware update, I'd definitely want to try and fix these as I've since removed them as a test. It's really frustrating. 

 Also, have the same issue, I have 6 of these, 4 upgraded to 1.4.2 and I was no longer able to connect to them with Python-Kasa or Python Tapo libraries as before. The other 2 were working fine still (on 1.2.5, I believe), then they upgraded before I could disable auto-firmware updates, now all 6 are on 1.4.2 and all my automation scripts have been rendered useless now.

There have been numerous posts all over GitHub about this, and some people have gotten 1.4.4 on their plugs somehow, and they started working for them. I have been unable to get mine to upgrade to this supposed new 1.4.4 firmware, but TP-Link has no documentation anywhere that it actually exists.

How do we get this fixed? We need the 1.4.4 firmware rolled out immediately! Where is it?