@blrvenky 

Good Day,

Thank you very much for your patience.

May I know your modem number is TD-W8961N or TD-W8901N?

For your case, please refer to the following suggestion:

1. connect the computer via a cable to the TD-W8901N;
2. check the IP address and gateway on the computer; if possible, you could share a picture here;
3. try to ping the gateway  and tplinkmodem.net

Thank you~

Iam unable to open the page of default gateway 192.168.1.1 - Model is TD-W8901N

Attached the images which you asked for

With static IP assigned to laptop

ping result of gateway

image of TD-W8901N

I found a method where i can get access to management site. 

Press the wireless button and power  ON the device and hold for few seconds, then release the button, only Power ON, WIFI and LAN connected PORT LED will be ON.

At this stage can access the management page. during this phase  did a  reset to factory default and when powered ON  again same problem.

Followed the same method metion above  and did a firmware update. 

After this  also same problem unable to access default page. 

Why does the management page is accessible only  during this method - Press the wireless button and power  ON the device and hold for few seconds?

Thanks

Venkatesh

Any suggestion  and fix to this problem 

Firmware version on the device is 1.0.0 Build 141114 Rel.28062

@blrvenky 

Good day.

Sorry for the delay.

I guess you might accidentally get into the firmware recovery mode.

May I know how long have you had the modem?

If it is still under warranty, it’s time to contact the shop retailer to get it replaced.

Thank you very much.