Did you configure TL-WA850RE at extender mode?

If yes, the password should be the same as your home network.

Hi Bowen98 and thanks for your answer. It seems the problem may be related to the MacOS system, since my flatmate is using Windows and he had no problem at all (meaning the password is the one supposed to be). Do you know if there is some extra configuration I should do?
Thanks!

I have the exact same problem with MacOS (macbook pro 2011).
Interesting: after reseting the tp-link i could connect to device to make quick installation. Because there is no password for connection — no problem to installation. But after installation — "the password is incorrect" (((

Nuraang wrote

Hi Bowen98 and thanks for your answer. It seems the problem may be related to the MacOS system, since my flatmate is using Windows and he had no problem at all (meaning the password is the one supposed to be). Do you know if there is some extra configuration I should do?
Thanks!

try other web browser?

Solution: I have update soft on TL-WA850RE (you could download it from the tp-link site) — and everything became OK.

Hi - I was on the downloads area and can't find the Mac upgrade. Can you tell me does it upgrade the powerline extender via your Mac? Mine is TL-WA860RE I have been using my iPhone using a browser and the TPLink webpage with the ip address. I get the router paired by running the scan for networks and find mine, run pairing, it says Finished, the lights are green and on full bars on the TPLink plug, the home wifi hub shows up the iPhone with full signal... and refuses the correct password (which works in another room) grrrr. I tried the home hub/router password and the BT roaming one just in case but no luck. Unfortunately there is an EE data dead spot in the street and drops out so it isn't a good option.