Model :

Hardware Version :

Firmware Version :

ISP :

Adapter: TP-Link TL-WDN4800
Router: Asus RT-N66U
OS: Windows 10


After a Win10 update and reboot yesterday, I can no longer connect to my 5GHz network. The error I get is "Can't connect to this network" (different from wrong password). I can still connect to the 2.4GHz one, but it's MUCH slower. Other devices can still connect to 5GHz, including another Win10 desktop with an identical TL-WDN4800 adapter (and the windows update), and a laptop right beside this computer.


I have tried:
Made Win10 forget all networks via Manage known networks

Swapped the TL-WDN4800 adapter card with the one in the working computer (neither card works in this computer, both work in the other one)


Uninstalled and reinstalled adapter driver, including two Qualcomm Atheros 2016 drivers that seem to come with Win10, and these official drivers from 2014: http://www.tp-link.com/us/download/TL-WDN4800.html#Driver


Updated router firmware


Uninstalled windows update KB3213986


Rolled back to an earlier System Restore Point several reboots before the issue occurred


Any other advice? Is there some way to get more detail than "Can't connect to this network"? Or some way to thoroughly reset all Win10 networking settings? Are there other drivers I should try? Some obscure router setting I can't find?