Hi, 

I recently bought Tp-Link PA4110 (powerline adapter) and TL-WPA4220 AV500 (wifi powerline extender). On my third floor, I connected PA4110 to router, and then paired it with with the 4220. It worked fine.

However, the connection does not reach to second floor. I tried moving the 4220 to second floor, and the connection worked fine, which means it is in same electrical circuit. But if I put on the second floor, it does not reach the third floor. 

So I bought another TL-WPA 4220 (call it Second TL-WPA 4220), expecting that I can just pair it with the first Tp-Link PA4110. I can see that the Powerline LED is on, the Wifi LED is on, and when I find the SSID on my devices, I can connect. But every time, it keeps on saying "Failed to Obtain IP Address". 

Two questions: 

1. Is buying a second Wireless Power Adapter the right way to do it? So basically I now have 1 unit of 4110 and two units of WPA 4220 

2. Should I pair the Second WPA 4220 with the first PA4100? Or do I need a second PA4110? 

2. What does it mean by Cannot Obtain IP Address? 

Your help in this would be greatly appreciated. Thanks!