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Tapo P125M: Local API Auth Broken After Firmware Update (Error 1003 at Handshake)

Tapo P125M: Local API Auth Broken After Firmware Update (Error 1003 at Handshake)

Tapo P125M: Local API Auth Broken After Firmware Update (Error 1003 at Handshake)
Tapo P125M: Local API Auth Broken After Firmware Update (Error 1003 at Handshake)
a week ago - last edited a week ago
Tags: #Firmware
Model: Tapo P125M  
Hardware Version: V1
Firmware Version: 1.4.2 Build 251204 Rel.103056

Two of my P125M (US) plugs stopped working with local third-party control after a recent firmware update. They still work fine in the Tapo app and the credentials are correct, but any local API connection fails immediately during the handshake with:

 

Unable to complete handshake: TRANSPORT_UNKNOWN_CREDENTIALS_ERROR(1003)

 

The device rejects the session at the key-exchange step, before any login is even attempted, so it's not a wrong-password situation.

 

What I've already tried, none of which fixed it:

  - Toggling Third-Party Compatibility off and on in the app

  - Fully removing and re-adding the plugs to the same account

  - Rebooting the plugs and the host 

  

This looks like a firmware regression in the local AES auth on the P125M. Several other users are reporting the same thing on Home Assistant (issue #173171), and there's a matching report for the P110 on firmware 1.4.x here: https://community.tp-link.com/en/smart-home/forum/topic/863296

 

Could someone from TP-Link confirm whether this is a known firmware issue and whether a fix or rollback is coming? Happy to provide firmware/hardware versions or logs.

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#1
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1 Accepted Solution
Re:Tapo P125M: Local API Auth Broken After Firmware Update (Error 1003 at Handshake)-Solution
a week ago - last edited a week ago

As of this morning updating to v1.4.4 Build 260521 Rel 100818, the issue is resolved. Currently only 1 of my plugs has the update, assuming there is a rolling deployment.

Recommended Solution
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#3
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5 Reply
Re:Tapo P125M: Local API Auth Broken After Firmware Update (Error 1003 at Handshake)
a week ago
I am having the same error since the firmware update, I was going to buy more because they were working so well for me, now I’m holding on until a solution is found otherwise I am going to look for another manufacturer
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#2
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Re:Tapo P125M: Local API Auth Broken After Firmware Update (Error 1003 at Handshake)-Solution
a week ago - last edited a week ago

As of this morning updating to v1.4.4 Build 260521 Rel 100818, the issue is resolved. Currently only 1 of my plugs has the update, assuming there is a rolling deployment.

Recommended Solution
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#3
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Re:Tapo P125M: Local API Auth Broken After Firmware Update (Error 1003 at Handshake)
a week ago

  @mrosoff @Garqua 


I should mention that usage methods like this, or integration with third-party platforms such as Home Assistant, are not officially supported. If your Tapo device isn’t connecting in that setup, there is a “Third-Party Compatibility” switch within the Tapo app that you can try turning on to see if it helps. Frequently asked questions about the "Third-Party Compatibility" feature

 

Please be aware that enabling this feature may introduce potential security risks, and we cannot guarantee successful pairing with unofficial third-party platforms.If that doesn’t resolve the issue, I’d recommend seeking help on the relevant third-party platform’s forum or community.

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#4
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Re:Tapo P125M: Local API Auth Broken After Firmware Update (Error 1003 at Handshake)
Thursday

  @Wayne-TP When will all plugs get this update? I have 1 plug stuck on a lower version which is causing this issue for myself.

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#5
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Re:Tapo P125M: Local API Auth Broken After Firmware Update (Error 1003 at Handshake)
5 hours ago

talormanda wrote

  @Wayne-TP When will all plugs get this update? I have 1 plug stuck on a lower version which is causing this issue for myself.

  @talormanda 

 

We don’t have a specific timeline for firmware releases. As a new firmware’s gradual rollout expands, an increasing number of devices will be able to detect the update. Your patience is appreciated.

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#6
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Helpful: 3

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Replies: 5

Tags

Firmware