What should I do if I fail to login Archer MR400(EU)/Archer MR200(EU)v2’s web UI?

Troubleshooting
Updated 10-11-2017 03:23:04 AM
This Article Applies to: 

If browser’s language is Russian, Italian, German, Turkish, or Polish, web server won’t respond when click ‘login’.
We have released new firmwares to fix the bug (Archer MR200(EU)_V2_170927, Archer MR400(EU)_V1_170907), please refer to the one of following two methods to upgrade: 

Method 1: Via Web UI 
1. Please change the browser’s language to another one (Chrome is recommended), 
https://support.google.com/chromebook/answer/1059490?hl=en
2. Refer to the link below to upgrade the firmware:
http://www.tp-link.com/en/faq-1667.html

Method 2: Via Tether
Please connect smartphone to TP-Link’s wifi, then open Tether and enter the username and password to login the TP-Link device (They are the same as the login credentials for the web management page. The default Login username and password are both “admin”.)
Go to ‘ Tools – System –Firmware Update’ to upgrade the firmware.