UPDATE: I feel like I had to update my existing review of this product because what I wrote before no longer applies, even though the original review was accurate. I was readying this Eero extender to return it to Amazon, but thought I would try one more time to get it to connect to my gateway. I went through all the steps to install it using the Eero app and got to the point where it had always failed before, expecting it to fail again. As I said in my original review, before the app detected the extender, but the extender simply wouldn't pair with my gateway. This time it did. I have no idea why. I didn't do anything differently than I had many times before. But for whatever reason, this time it worked, and was painless, just as the positive reviewers of this product said it had been for them.
Had it worked this painlessly for me when I first tried to install the extender, my initial review would have been glowing. The extender works well, and has extended our wifi signal much farther than our old extender we used with a different router. The mesh network extended our signal to the far side of the house from our gateway, and it's the first time I have ever had a strong wifi signal in my studio. This works, and it works well.
I changed my overall rating to 4 stars. I'm impressed with the Eero extender itself now that it's working properly. But I couldn't do 5 stars because of the frustrations. As I've mentioned, I have an associate degree in computer programming and certifications in network management and troubleshooting. I still have no clue why the unit wouldn't install over that first frustrating week I repeatedly tried. All that said, though, I'm glad it finally did, and I'm very happy. So in conclusion, I'd say that when it works, it is a painless install, and the unit works well. But it seems it's a possibility that installation won't work at all, and the error message it gives you when installation fails is not helpful. So when it works, it works. When it doesn't? Well...
ORIGINAL REVIEW:
I hate to leave a review on something before I've exhausted all avenues of getting something to work, but for something that's promoted as being easy to install, so far this Eero extender has been anything but. The app does not detect the Eero extender, but I can find it by scanning the serial number (see attached photos). But from there the app will not connect to the Eero extender, and the extender simply sits there flashing blue. I have power cycled both the extender and my main Eero gateway, and nothing makes any difference.
The only thing I can think of is possibly that our cable provider supplied the gateway Eero. But they didn't think adding an extender I bought on my own would be a problem. In fact, the tech recommended it.
As for the recommended troubleshooting; "Bluetooth is off": nope. "Multiple eeros found": nope. "No eero found": I have to scan the serial number, but the app finds it. "eero already registered/on a different network": hard reset doesn't work, "proceed to hold down the reset button until the eero blinks red" doesn't work, extender never flashes red, it simply resets to the flashing white and then the flashing blue. "Poor connection": Nope - my second computer, which is all the way on the far side of the house from the Eero gateway connects just fine, even if it is a low signal (which the extender was supposed to help with). "Connect your additional eero via Ethernet to the gateway eero" cannot work because there's no ethernet port on the extender.
In the end, this has been very frustrating, and it's not supposed to be (or so I'm told). I have an associate degree in computer programming and a certification in networking and a CompTIA A+ certification. I'm not stranger to tech or networks. If this thing could be made to work, I could've made it work. My frustrations about trying to install something which some people have said is largely as simple as plugging it up and using the app to install it your network is the main reason I'm writing this review.
I still hope to get an Eero extender working on our network. I've very much liked our Eero gateway so far. It's faster and more stable than anything we've used prior. But I'm beginning to think this one is defective, and is a good reason why people should, perhaps, be wary of refurbished electronics. For myself, I'm at a point where I'm not sure if I'd rather have a replacement or a refund. I think this is probably one of those things where it either works flawlessly or it doesn't work at all, and there's no in-between. lol. Anyway, I just wanted to provide a frustrated tech guy's perspective on when it's the latter.