Please first connect your network card to the wireless router using an ethernet cable (also known as a LAN cable).
In order to gather essential troubleshooting information about your wireless card, please follow this procedure:
Open Terminal from “Applications->Accessories->Terminal”
Please copy-paste the following diagnostic command from thehttps://help.ubuntu.com/community/WirelessTroubleshootingProcedure website using Chromium or Firefox into the Linux Terminal. The command STARTS with the word sudo and ENDS with the word lsmod. So please copy-paste the ENTIRE diagnostic command below from Firefox into a Terminal, press <enter>, then enter password when sudo asks for password, then press enter again.
Tip: If you have a wheel mouse or 3 button mouse you do not need to type commands into the Terminal. Highlight the diagnostic command written on the page. Move your cursor anywhere in the Terminal and press the wheel or middle button. Automatic Copy and paste! No spelling mistakes! No Typos! No other errors!
sudo apt-get update; sudo apt-get install hwinfo grep; sudo lshw -C network; rfkill list;
sudo iwlist scanning; cat /etc/network/interfaces; cat /etc/lsb-release; lspci -nn; lsusb;
sudo lshw -short; uname -a; dmesg | egrep 'acx|at76|ath|b43|bcm|CX|eth|ipw|irmware|isl|lbtf|ndiswrapper|NPE|ound|prism|rtl|rt2|rt3|usb|witch|wl';
iwconfig; grep b43 /etc/modprobe.d/*; grep wl /etc/modprobe.d/*; sudo hwinfo --netcard ;
cat /var/lib/NetworkManager/NetworkManager.state; sudo lsmod