What's the firmware version you downloaded? Did you restore it to factory defaults and reconfigure it? Some firmwares will take effect after that.

Ada wrote

What's the firmware version you downloaded? Did you restore it to factory defaults and reconfigure it? Some firmwares will take effect after that.

the version is : 2.0.0 Build 120222 Rel.08176.
I also tried restart with factory defaults, but nothing happens.

the version is 2.0.0 Build 120222 Rel.08176
I restarted with factory defaults

You misunderstand what I mean... What's the firmware version you tried to download and upgrade? Can you provide a link?

I downloaded and upgraded with this one :

TD-W8961ND_V2_120427
Published Date 4/27/2012

Try following steps:
1. Click Start -> Run to launch the command line interface.
2. In the text box, please input cmd.
3. In the command line interface, please input telnet 192.168.1.1
For Windows Vista & 7, please go to “Control Panel – Program – Turn on/off Windows Feature”, Enable “Telnet Client” service.
4. Input your username and password: admin admin
5. Input the command sys modelcheck off.
6. Now go to the web page and upgrade the new firmware.
7. After upgrade/reboot, go to “SysRestart” to restore factory default once, or the new firmware(function) won’t take affect

Many thanks for you reply Ada.
By the way, I have windows 8.1.
When I type 'cmd' in run and then type 'telnet 192.168.1.1' it doesn't work





Can I use the same method like windows 7?
let's suppose if the update is successful, is there any harm in restoring my current settings from a backup instead of inserting them manually?

by the way, I have windows 8.1, the command : 'telnet 192.168.1.1' doesn't work.

Telnet doesn't work because it is not enabled I think. Start—>Control Panel—>programs and Features-- Turn Windows Features on or off. Choose telnet client, Press OK.
It should not but some special firmware may need to reconfigure manually.

thank you so much for your replies. I'll try and tell you the result.