Updated Sep 2022
The RE550 V1 Build 220727 official firmware has fixed this problem.
Please update the firmware for your range extender to the latest one.  

If you can not see this firmware or failed to open the above URL, check the marked solution of this thread.

Moderation note: This topic will be closed for further comments or replies. You can use the search bar to find a similar topic, or Start a New Thread if you would like to provide additional feedback with the range extender. 

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This Article Applies to:

RE550_V1_211110 RE450_V4_211207

Issue Description:

With Onemesh enabled, after managing RE550 V1 in the Tether app for a few minutes, the app may quit or force to log user out and prompt errors below:

1. "Session timed out. Please log in again" 2. "Unable to connect to the device, please try again. "

Note: the Web UI of range extender still works fine, you could log in the web page of RE to manage or change settings.

Solution :

Updated Sep 2022

The RE550 V1 Build 220727 official firmware has fixed this problem. Please update the firmware for your range extender to the latest firmware. If you can not see the firmware or failed to open the above URL, download firmware from here: RE550(EU)_V1_1.0.11 Build 220727 RE550(US)_V1_1.0.11 Build 220727

For RE550v1, here comes a beta firmware to fix the issue, you may download and install the beta firmware to determine if the issue gets resolved.

Note: 1. The beta firmware is universal for RE550 V1 of different country versions.

2. Please check the device label to verify the hardware version of your device first, and be sure yours is RE550 V1. 

3. Be sure you have read the Terms and Conditions for TP-Link Beta Firmware before proceeding!

If you refuse to install the beta firmware on the extender, you have the following solutions also:

1. Use the Web UI to manage your range extender instead of the Tether APP. 2. Temporarily turn off OneMesh feature to manage your extender in the Tether APP.

If the issue persists after following the above suggestions, please start a new thread and provide information

1. Model number of router & Range extender ; hardware & firmware version of router and extender.

2. Is OneMesh ON or OFF on your range extender?

3. A photo of error message on the Tether APP.

More Articles: 

TP-Link Range Extender Setup (Range Extender Mode)

Has connected to TP-Link extender but no internet, what can I do?

What should I do if Internet speed becomes slow via Range Extender?

Unable to Connect to WiFi Extender or Saying Incorrect Password

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