I have four TP-Link powerline adapters: two TL-PA2010 v1.1s , and two TL-PA4010P v2.0s, all with the latest firmware. I am trying to use them to extend my Wi-Fi coverage outdoors using a couple of old routers. My original hope was to save one adapter for getting Ethernet to my PC, but I'm having trouble getting everything to work with just three.

There are three connection points where I need to install the adapters:
Point A is in my house connected to my main internet router.
Point B is in an outdoor building connected to a router in AP mode.
Point C is in another outdoor building connected to a router in AP mode.

All points are on the same circuit. However, I am having some difficulties getting them all to connect.

If I plug them all up in the same area, they are all able to communicate with no issues. I've tested A with B, A with C, and B with C one on one as well to ensure that they are all on the same network.
The problems start when I try to connect them up at each location. If I connect A to B first, then C is unable to connect. If I connect B to C, then A is unable to connect. If I try to connect A to C first, they aren't able to connect. The distance between point A and C is only ~150 ft.

I'm unsure as to why this isn't working. It doesn't make sense. They're all on the same Powerline network and electrical circuit. :confused:

I was able to setup a workaround by using a fourth adapter, D. I paired A to B, and C to D to make two Powerline networks. I connected adapter D to a switch port on the router that was connected to adapter B, and that allowed everything to work. However, I don't really like that solution, since it requires four adapters when it should only require three.

If there's any additional information I could provide that would help, please let me know. I can attempt to create a diagram as well. :p

Thanks!