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I'm running Ubuntu 9.10 and after a recent reboot, I'm now unable to authenticate to wireless networks using WEP encryption.

I can connect fine to open networks (no idea about WPA).

When trying to connect via WEP, I'm continually prompted for the network key, which I know I have entered correctly (and should have been/is saved in my keyring anyway).

Everything had been working fine until the reboot. No updates had been installed or configuration changes made.

Hardware-wise, everything looks fine, and the fact that connecting to an open network works just fine leads me to think this is a software issue.

I just don't know where to begin fixing it.

Any insights would be greatly appreciated.

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Have you tried to connect to more than one network? – Fred Mar 31 '10 at 17:14

Perhaps your WEP connection is 64-bit. The Ubuntu GUI no longer supports 64-bit WEP connections for security reasons (it is VERY insecure).

Anyhow, you can try setting up via the command line interface (terminal):

sudo /etc/init.d/network-manager stop
sudo iwlist wlan0 scan
sudo iwconfig wlan0 essid [networkname]
sudo iwconfig key [0123456789] open
sudo dhclient wlan0

Do not include the [ ] brackets, this is where you need to enter your info. Your 64-bit key should be TEN hexdecimal characters.

Hope this helps.

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