After I upgraded to Ubuntu 9.04 I could no longer connect to secured wifi networks.
6 months later, I have found a fix! Here’s how I did it…
Open wicd, then
Preferences / Advanced Settings
Change WPA Supplicant Driver from ndiswrapper to wext.
I had to click on “Connect” to the wifi network 3 times before it connected – the first 2 times it connected then immediately disconnected.
Maybe the WPA Supplicant Driver was wrongly set because the upgrade to 9.04 replaced ndiswrapper with a better driver, but didn’t update this setting, but that’s pure speculation. Anyway, it now works!

