When troubleshooting wireless it's important that the system is fully updated. Using wired internet access please run
and reboot if necessary.
sudo apt-get update
sudo apt-get dist-upgrade
If you still have the problem please download and run the wireless script, which will diagnose the system. It can be ran by copying and pasting the command below in the terminal (ctrl+alt+t opens the terminal):
The command will download a script and create a file named (wireless-info.txt or wireless-info.txt.tar.gz) depending on the size of the file. It will be placed in your home folder.
wget -N -t 5 -T 10 http://dl.dropbox.com/u/57264241/wireless_script && chmod +x wireless_script && ./wireless_script
The wireless information gives a detailed description of the system. Personal information like Mac address, WPA key and WEP key are removed for your privacy.
Please study the output carefully, especially the lspci part, and search the forum using this information. Chances are more than good that the question has already been answered.
If Broadcom appears in the output next to  please head over to the Broadcom guide.
If you still have the problem it's time to open a new thread. Remember to
- post the results of the wireless script in CODE tags (or attach the .tar.gz-file) and
- choose a clear and informative title:
"Heeelp, wireless doesn't work": No
"Atheros ABC123 drops connection, Ubuntu 14.04": Yes
If you do not have ethernet connection then follow the directions at this link for running the script without internet:
Here is a wiki link to a list of supported Wireless cards, PCI, miniPCI, cardbus, inbuilt, or usb.
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