I don’t know why I couldn’t add it sooner, but my girlfriend’s Wi-Fi seems to be acting weird with her new computer. The computer randomly disconnects from the internet and sometimes on startup (this is the more common of the two) and displays the above message.
After clicking on the Wifi icon at the bottom right of the taskbar, click on “Network settings” just above the Wifi on and off button. After being redirected to settings, click on “Manage Wi-Fi settings” just below “Advanced options”. Now once you reach another window, scroll down until you see the Wifi network you were unable to connect to. Click on it and click “Forget”. After that, reconnect to the same Wifi network and re-enter the password. It should connect smoothly. It did the same to me and I was on the verge of madness. I hope this helps you!
Go to the command prompt (cmd) run it as administrator and type “netcfg -d” without the ” and restart your PC.
They probably changed the password and/or restarted the system.