@UnWired 

Have you tried reinstalling the utility and also tried viewing the utility on another computer?

@Tony 

Thank you for the suggestions.  (Sometimes I worry that "no one is listening" on community forums.)

This was a fresh install, but I certainly can install it again and also install it on another computer.  (Ironically, the fresh install was because I updated Wireshark to the latest release which changed the packet capture software and erased the PCAP that tlPLC uses.)  Will report back later today.

I was just "blown away" when adding a fifth PA9020 did this.  The PA9020 is supposed to support up to 16 adapters on one network.  When I remove it, the problem goes away and the four original PA9020's all report transmit speed to the other three.  When it is on the network, the main adapter reports speed to the other three, but the other three report speed only to the main, not to each other.

Thanks again.  Will get on it.

@Tony 

OK.  I installed the Utility on two more computers (1) Windows 7 (which won't be Windows 7 next month) and (2) Windows 10 laptop.

Both do the same thing.  Transmission FROM the unit these are all connected to shows transmit speed to all the original units, and those three original units all show transmission speed to the main node and to every other unit.  As soon as the new PA9020P is plugged in, the main unit continues to show everything, but ALL other units (three original and one new) all do the same thing.  They show transmit speed to the main unit, but not to each other (question mark).

Damn.

Before posting here, I did an online chat with TP-Link support, which was sadly disappointing.  The chatter (am I the chattee?) insisted that the "Home" icon had to light up, even though I pointed out that the PA9020 has an LED (that IS green) and the icon itself does not light up.  He (she?) then insisted that I needed to plug the unit into another electrical outlet, even though the Home LED was green, and closed the chat session.  Telling me that I can call the 800 number for more support.  Very frustrating since the tlPLC utility clearly shows transmission rates above 1GB to and from this new unit.  They should be, because they are in the same room on the same electrical circuit.  And, I did move it to another outlet (in the same room, on the same circuit) and got the same results.

I think either (1) the utility doesn't handle more than four units well or (2) there is some incompatibility between V1 and V3 Powerline adapters (as far as the utility program is concerned).

I guess that I can carry the laptop around the house, plug it into each Powerline unit and see what happens.  Not thrilled because (a) this involves crawling around and sticking the ethernet plug "blindly" up into the jack, and (b) I observe that the reported transmission rates vary a lot from minute to minute.  I had wanted to sit here and check from time-to-time, "what are the speeds NOW?"

Any ideas?  I'll try almost anything.

@UnWired 

The question mark could be a result of a bad connection, but if the added powerline adapter is green, then its not that.

Another reason could be if there is no data transmitting from that 5th adapter. Once the powerline light is green, connect your computer to it, and stream a youtube video or something similar. While that is being done, run the utility. do you still get the same symptom? If so, I can get back to HQ as what you brought up is consistantly happening no matter what you do.

@Tony 

I did plug the PA9020 into a couple of other electrical outlets and verified that the strange behavior exists.  Creating a data stream is a good idea, and I will do that today.  I am not confident that data flow is necessary because one of the adapters is only supplying connection to a Tivo mini in a bedroom.  The TV is usually off and the Tivo mini pretty much inactive, so I doubt there is very much data moving through the adapter (except for the goofy background chatter).

My other thought is to temporarily disconnect one of the four V1 adapters and connect the new one it its place.

Wonder if it causes a problem to run the tlPLC utility from multiple PC's at the same time?

@UnWired 

This has been truly instructive.  I removed one of the V1 PA9020's and replaced it with the new (V3.8) one. tlPLC utility "works fine".  Click on any of the four units and see the transmit speed to the other three.

This seems to have narrowed the problem to "Four Units Maximum" on the tlPLC Utility, as far as PA9020's are concerned.  Not what I had wanted to find.

THANK YOU for commenting on this problem.

I am happy to perform any tests the engineers think would help.

I also noticed that when there are more than four units on the display, they are not laid out very well and information gets "hidden".

@UnWired 

Thanks.  I had imagined that someone would fire back a screen shot of 16 PA9020's with the comment, "duh.  So THERE."  Then, I would have to come back with, "but, did you try it with a mix of V1 and V3 adapters?"

Even though Powerline is not what I "had hoped for", it is a TON better than crawling through the attic and installing firestop devices in several ceilings and walls to pull ethernet cable.  Those firestop gizmos are only sold in packages of 10, and I need two.  Plus one of the extendable pull stick things to grab the cable in a place I cannot crawl to.

@UnWired 

The mystery continues.  Had another "Red Out" and reset.  Today, I noticed that the tpPLC utility reports throughput in one direction between two adapters but "?" in the other direction.

The link is certainly up and working.  My security camera app can open four cameras that are connected to the "Garage" adapter and display live video.  So, traffic flows both ways. 

And, yes, I am now so paranoid about not noticing a Red LED that I keep the app open on my machine and check it several times a day. 

@UnWired 

I forwarded this to our testers, but due to the holiday in China it might take some time to finally get a result.

With respect to the red LED, that would be the powerline letting you know that the link speed is dropping below 50 Mbps when connected to that outlet.