[SOLVED] Not your basic 'can't connect to home wifi' question

[matrimforever]

Hi,
I'm an intermediate computer user and know how to troubleshoot a lot of network issues. The problem is with my daughter's laptop, which USED to connect to my home Wifi fine, but today she came over and got the "Unable to Connect to Network error". I IMMEDIATELY thought...okay easy one to fix, just 'Forget the network' and reconnect. Nope. Here's a list of what else I've tried:

-Uninstalled the driver/reinstalled
-Rebooted the router
-RESET the router to factory defaults
-turned off the 2 frequencies 2.4 and 5.8, turned them back on
-disabled the wifi adapter on the laptop, re-enable
-changed the SSID
-network reset
-all other computers can connect to router fine
-updated what i thought was the Wifi driver from hp.com (i say thought because it shows 'Realtek' as the driver, but when I uninstall and it self reinstalls it's an Intel
-it CAN connect to my router's Wifi GUEST network successfully, just not my regular home network(she has to connect via a browser to gain her access like a motel)
-There is no MAC filtering or weird DHCP reservations
-There is no antivirus installed that may be blocking connection - Windows Firewall has been turned off as well.

Again, the weird thing is it can connect to other wifi networks fine, including my router's GUEST wifi, just not the regular home wifi(and it used to).

Laptop is an HP Elitebook 840 G2

Any other ideas are appreciated. I haven't updated the BIOS because I got it off someone and they left the BIOS pw protected :/.

 

[matrimforever]

No one has any other suggestions?

 

[bill001g]

This is likely some strange bug in windows. I am going to bet if you were to boot a USB linux image it would connect.
It is not going to be anything with a firewall or dhcp or addresses. It is purely something related to the wifi networks.
Hate to say it but likely the fastest solution is going to be to reinstall windows.

 

[matrimforever]

Bummer, well thanks for the reply.