@horace_vr 

Below is the instruction to setup the WDS feature to boost the wifi signal. 

https://www.tp-link.com/support/faq/227/

Please use the same password of the main router ( Archer C2) to configure it and please notice that you need change the IP address to another one cause they are 192.168.0.1 by default.

May it help. 

Thank you. I followed those steps, but can't get it to work. I also made sure the IPs of the routers are different: 192.168.1.1 (Client) versus 192.168.0.1 for Archer (Main).

WDS status is 'Run', but the ping is not working...

@horace_vr 

You need give TL-WR1043ND a different IP address but it still should be in the same subnet, In other word, if the Archer C2 uses 192.168.0.1, you can give 192.168.0.100 to the wifi-to lan adapter router. 

May it help. 

@Kevin_Z 

Thank you for trying to help out here.

The 1043ND does connect to the Archer, as I can  see its MAC under the Archer's "Wireless Statistics". However, the 1043ND does not output Internet Connection. I can connect to the 1043ND's network, but I can't connect to the Internet.

(of course, I checked and Archer has Internet connection)

Later edit:

this FAQ: https://www.tp-link.com/us/support/faq/227/

says at step 10 that there might be some incompatibility between the 2 devices. Looks like I am among the un-lucky ones, unless I am doing something wrong...

@horace_vr 

I see, thanks for your reply. The configuration steps are correct, but there is still no internet access. 

You can try to swap the location of the two routers to give it a go, otherwise, you may order another network expansion device, like range extender or powerline adapters to boost the wifi signal. 

Or you can configure the TL-WR1043ND as the access point by connecting it to the router by wired cable. 

Good day.