Can't. Sign on to WiFi

On the back or bottom of your wifi router there is an ip address that will look something like this: 255.0.150.121 (this is just an example, the numbers will be different). Write it down and save it.

Go to the computer and open a browser. Type the ip address into the address bar at the top of your browser window. This will take you to the settings for your wifi router. It will ask for a password at some point, but %99 of wifi routers have no password as default. Leave the user name alone (if it's blank, leave it or if there is something there, leave it there) and then leave the password blank and log in. From there you can restore settings to factory defaults, add/change passwords for your wifi and other administration type options. First try removing or changing the password (same difference) and then save the changes and exit the browser. Disconnect any networks that may be saved and reconnect using the new password (if you didn't remove it). If this doesn't work, go back to the wifi admin settings by repeating the process of entering the ip address into a browser. Then go to the bottom and there will be an option to reset to factory defaults, do this and reset the computer and the wifi router after the changes have been saved and the browser has been closed.

Hope this helps, let me know! I'll be glad to help further!