I’ve been trying to figure out why a joint WEP & WPA encrypted Wireless Network has been failing to work on Ubuntu Linux.  After much delving, i realised that the key was set to 2, and the standard network config GUI did not provide an option to select the key you wanted to use.

If you experience a similar problem, it’s really easy to resolve… I wish i’d had access to this information yesterday as it would have saved me several wasted hours delving into various config files and head scratching!

All you need to is

• open a terminal window
• type “pico /etc/network/interfaces” without the quotes
• if there’s a line reading “wireless-key xxxxx”, change it to “wireless-key2 xxxxx” replacing the “2″ with your wep key id.
• Now save the changes and exit to the terminal.
• Type “sudo ifdown wlan0″ and press enter.  This will stop the card if it’s started.  If you get an error, ignor it - the card probably isn’t started.
• Type “sudo ifup wlan0″ and press enter.  This will start the card again.
• Type “ping google.com” and press enter.  You should now be connected to the internet.

If this doesn’t work, i’m sorry!  It worked for me after many hours of tinkering, so all i can say is - persevere.

Good luck!