try another computer or browser? never heard of this. you can contact tp-link support for suggestion.

Hi. Have you solved this problem yet? I think that you may have the same issue as me. If it is the same issue, then using another computer or another browser will not help.

My issue started when I upgraded the firmware to the latest release for my model. Afterwards I no longer had access to the web UI to manage the device. My device is a WDR3600 configured as a WAP.
It is still working well as a WAP on my home LAN, providing wifi access to my modem from Win 10 PCs and laptops, Chromebook, Android phones and guests' IOS devices. I just cannot log in to manage it anymore over wifi or over ethernet. I could use either before. I have also tried with different browsers.

My WAP has a fixed IP address. When I ping this address over wifi from my laptop or over ethernet from my PC I get 'Destination host unreachable'.

Checking online forums I have learned that this problem is quite common and worse it is reported that TP-Link has not addressed the issues.

Was the management UI function working prior to your issue? Did you upgrade your firmware?

Shouldn't it be 192.168.1.1 ?

Since seeing this and responding I noticed there are 2 threads with this issue,

Looking at the AD7200 issue it says to use 192.168.0.1 but it also says to use 192.168.1.1 if that fails, however chaps I would suggest you check your browser cookie settings as a no cookie policy will prevent you logging in to the router page, hth.