Hi all, I have a possible solution where you don't need to assign any static IP-addresses to anything.

INTRODUCTION:
I had the same problem as the topic starter: when I try to connect on the wifi-network when I'm in the zone extended by the TL-WPA4220 I do not get internet access and when checking the network details I see that an IP-address in the 169.x.x.x, subnet 255.255.0.0 has been assigned, while the rest of the IP-addresses is in the 192.168 range. At that point, internet stops working on all my devices connected to the network and I have to reboot my router to get it to work again.

This problem started when I updated the firmware of my router (Fritz!Box). Before that I had this network set-up working for 5 months, so first I thought it was the routers new firmware's fault. Then I spend about 6 hours over 3 days trying to solve it with downgrading the firmware of my router, restoring factory settings, upgrading firmware of both the router, WPA4220 and PA4010, restoring my routers back-up settings from before this all started, and several combinations and repetitions of this. In the end, when I almost threw the kit away due to frustration, I got it to work, so let me share with you what my steps were.


SOLUTION (SHORT VERSION):
Try this:
1. Make sure the WPA4220 and PA4010 are paired and connected to the router, and that WLAN on the WPA4220 is TURNED OFF (by manually pressing the WLAN button for 5 seconds, the light should not blink but be off.)
2. While your computer is connected to the WPA4220 via ethernet, run "Powerline Scan.exe" and click "connect" (called "TL-WPA4220_V1_Powerline_Scan_Utility", see http://www.tp-link.com/en/download/TL-WPA4220_V1.html#Utility)
3. Manually turn on WLAN again, it should now work.

I think these are the most essential steps of what I did. Since I actually took some more steps before it all worked again, I am not sure the above 3 steps are enough, so if this doesn't work directly, try the longer solution which I will describe below. (I do not want to disable my network again to try it for myself, since I don't want to risk spending so many hours on this again ;) so please let us all know if this solution works if you are having these problems as well).

SOLUTION (FULL VERSION):
These were the steps I actually took after which it all worked properly again:
1. Factory reset WPA4220 (and the router, but this might not be necessary), and upgrade the firmware of the PA4010 and WPA4220 (and of the router, in my case Fritz!Box) to the most recent ones. (firmware TL-WPA4220_V1_160421 and TL-PA4010_V1_130821) I used the most recent tpPLC_Utility for this by installing the "PowerLineUtility.msi" file.
2. Connect your computer via Ethernet to PA4010 to assign the right network name that you will also use for your WPA4220. Take the PA4010 out of the socket.
3. Now put in the WPA4220 and connect your computer via Ethernet to assign the same network name and also put in the settings for your WiFi network (SSID, etc.), using also "Powerline Scan.exe" (see above). IMPORTANT: Turn off WLAN of the WPA4220 by manually pressing the WLAN button for 5 seconds, the light should not blink but be off. Then disconnect the WPA4220 from the socket.
4. Put the PA4010 in a socket and connect it to your router and put your WPA4220 in the socket where you want to set it up. Connect your laptop through Ethernet to see if internet is working (it should). Check your router settings page to see what devices of the TP-LINK set are connected to your router (note the MAC-addresses)
Do not yet turn WLAN on!!
5. Run "Powerline Scan.exe" and click on "connect" to go the the settings page of the WPA4220. Doublecheck if the WiFi network settings are still correct (it should be), but you don't have to do anything. Now check your router settings page again, a new device connected to your router should have popped up. (it did for me as soon as, and then only, I ran "Powerline Scan.exe", the device then stays connected for a while, but after 20 minutes to an hour it disappears again from the list of connected devices)
6. Turn on WLAN of the WPA4220 by manually pressing the WLAN button for 5 seconds.
7. Wait a little while (I did for half an hour, not sure if this matters anything)
8. Now connect your phone and other devices, they should again receive IP-addresses in the correct range. (it did for me)

So somehow, it seems by running the "Powerline Scan.exe" , you trigger a program in the WPA4220 that probably plays a role in assigning the right IP-addresses for WLAN. At least that's my conclusion from all this.
In the end I have a total of 4 different devices (each with its own MAC address) related to the TP-LINK KIT in the history of the connected devices list of my router. I guess 1 of them relates to the PA4010 and 3 to the WPA4220, of which 1 only gets activated by running "Powerline Scan.exe"

I hope this helps, please let us know if this does the trick for you as well.

Okay, I just found out the 4th MAC address is not linked to the TP-link kit, but is from a tablet I thought was turned off and connected automatically what I didn't notice. So forget the part about a new MAC-address popping up when you turn on the WLAN manually, I think that was just a coincidence on my end.

@evanA

Thanks a lot for the solution it worked (short version).

The network:
WAP4220 kit with two extenders
Extender1: WiFI on channel 5 same SSID as the router, static IP outside router DHCP range;
Extender 2: WiFI off. static IP outside router DHCP range
Router: WIFI on channel 3;

Connections:
Extender 1: IPAD + several windows mobile 10 + Several android + windows 10 laptop
Extender 2: Bravia TV connected by cable
Router: Windows 10 PC connected by cable + IPAD + several windows mobile 10 + Several android + windows 10 laptop

The mobile devices roam between extender 1 and router;

The problem:
Windows 10 laptop got limited connectivity after lease time, however if the extender 1 was dsconnected and connected again it worked until next lease time. An ipconfig /release /renew had the same effect as lease time (of course).
Don't know why only got problems with Windows laptop,

Solution:
besides the fixed extender IP had to perform evanA short procedure.

Now I have everything working for 24H with no problem.

The wpa4220 will assign itself the static ip 192.168.1.1 by default. Plug in one wpa4220, plug a computer into the Ethernet port, and go to that address to access the wpa4220. I think the default user is admin and password is admin. Your router usually has a self-assigned static IP address like 192.168.0.1. In that case I would assign the wpa4220 a static ip of 192.168.0.2, and if you have more than one wpa4220, continue with 192.168.0.3 and so on. Be sure to save changes and I think it will have to reboot, then manually go to the wireless page and configure the wireless on the wpa4220 to match the router (but use a different channel).

Hi All!

Wow Deployed a good number of the WPA4220 model and earlier models and never encountered this problem! EvanA's solution resolved for me. Just in case anyone has my scenario here's what I encountered...........

Ok so client wants to expand Wi-Fi around public building for staff and maybe public access. Keen to use PowerLine kit.

In my office testing I have existing TL-PA411 & TL-WPA4220 V1.0 set up with a TP-Link router model TD-W8980
I had to hand a TL-WPA281KIT V3 comprising of TL-PA211 & TL-WPA281 V3.0 units

My idea is to enable port grouping on the router (IE port based VLAN)

Ports 1-3 default IP Pool 192.168.1.x Default DHCP start at .100
Port 4 new public group IP Pool 10.44.0.x Default DHCP start at .100

Configure existing TL-PA411 & TL-WPA4220 with a power-line network name EG Staff
Configure spare TL-PA211 & TL-WPA281 with power-line network name EG Public

Then the TL-PA411 would be in say port 2 of the router and be part of the 192.168.1.x subnet
and the TL-PA211 would be in port 4 of the router and be part of the 10.44.0.x subnet

Set port group on the router up ok.

The TL-PA411 & TL-WPA4220 kit is up and running and has been for months the TL-WPA4220 had an IP set of 192.168.1.3 all good!

Here's where my day goes downhill........
Got the TL-WPA281 out and grabbed the 1st powerline utility disk I had to hand (not necessarily the one that came with the TL-WPA281 unit!)

As soon as I ran the Powerline scan utility I found I could NOT set the IP address of the TL-WPA281 unit and make it stick!
Ok so lets check out the existing, working TL-WPA4220 unit I think. Low and behold this has reverted to some random IP address out of the 193.168.1.x DHCP pool!

Today Following EvanA's solution seems to have resolved it.
I turned all PowerLine units off and apart from setting the Powerline Network name EG STAFF or PUBLIC I set the IP address of the TL-WPA4220 to 192.168.1.3 and the TL-WPA281 to 10.44.0.3. with the Wi-Fi of the powerline adaptors OFF!
With all plugged in and re-booted I new have two separate networks via the PowerLine and two separate subnets. Hurrah!
Access the PowerLine Wi-Fi Adaptors via there IP address above with Browser, NOT the PowerLine Scan utility, and turn on their respective WiFi All good! Big Hurrah!

I will test for a few days to see if these settings all 'stick' as I intend!

I conclude that with Wi-Fi on, the version of the PowerLine Scan utility I used was hunting the attached Wi-Fi subnet I'd initially started with or causing the Wi-Fi Powerline adaptors to do so (Smart Scan) IE 192.168.1.x (which will typically be the norm for most people or 192.168.0.x)
It's just trying to be too clever! the old acronym KISS comes to mind!

Another way to cope with this might be to assign some IP/MAC address assignments in the Router DHCP allocation pool. But that's boring! and in a large setup a pain!

I'm did not have any to hand but I thought some of the very early versions of the TP-Link Wi-Fi and an option for Static IP. (Might be wrong!) but it's definitely something that would be very desirable in any future firmware updates please!

I bought TL-WPA4220 Powerline Extender connected to a TL-WPA2220Kit.
I used to have wifi problems with WPA4220: connection dropping twice a day, broadcast/DCHP not assigning ip address, specially with IPhone and IMac (PCs and Androids less problems). Sometimes assigning static IP address would work (but not for more than 1 or 2 days) so I plugged another wifi router to the WPA4220 as a workaround.
A few days ago, I realized that my firmware (v1-EU) was not updated as I had thought. TPLink download page in Brazil didnt have the latest firmware version, it shows April,2014. Visiting TPLink page in Portugal I found a new firmware dated May,2016.
Both are same region v1(EU) and it worked for me. My problem is apparently solved.
http://www.tp-link.pt/download/TL-WPA4220.html#Firmware

Strange things.

thanks you for share!

Setting up a static IP was the solution and it allowed me to force an address outside the wifi/24. All clients were talking to DHCP just fine but the AP was invisible to scan probes! Whatever they have fixed it now refuse to accept my out-of-range ip and it now choose a random IP inside the wifi/24 instead. This bug was a exceptional feature, I was able to hide them all and I bought many because of it.It had a management interface, kind of, and now no more.

The powerline extenders can't accept the static IP address assigned by the router.
It only has a default IP 192.168.0.1 to manage it, if you are able to login to the management page, you can change it into the DHCP range of your router.