Wireless: network detected, but no connection

[Frank Lorenz]

On Mon, 2009-11-09 at 19:31 -0800, NoOp wrote:

> Sorry Frank; I'm stumped. 

I thank you anyway for your help! 

> So... over to anyone else with suggestions.

Meanwhile, I have new information about this problem and maybe there is
some hope. :-)
As i told in one of my previous post, this Wlan-stick worked on an old
laptop with Ubuntu 8.04.

Today I tried to run Ubuntu 8.04 from a live-cd and obtained the same
behavior: wireless network detected, trying to connect and failure about
a minute later. :-(

But, and here is the interesting part of the story, by clicking on the
NetworkManager icon, I selected the "Manual Configuration" and disabled
the "Roaming mode" by un-selecting  the "Enable Roaming Mode" option. At
this point, the other fields are un-grayed and I manually entered the
network name (ESSID) and selected "Automatic configuration (DHCP)
option.

The default value in the "Password type" option is "WPA Personal". The
other possible options are "WEP Key (Hexadecimal)", "WEP Key (ASCII)"
and "WPA2 Personal". There are NOT other options like "No Security" or
similar. I left selected the default value "WPA Personal" and simply
left the "Passsword" field blank.

After clicking "OK", a short "Changing Interface configuration" appeared
and... surprise surprise... the computer connects perfectly to the
wireless network. I was able to surf the web using Firefox and to ping
other machines without any problem! Wow! :-))))

OK, at this point I'm sure that the Wlan-sticks are not defective, it is
not a driver problem, it is not an interference or poor signal problem
and it is not a hardware problem. That's the good news!

The bad news is that I'm not able to replicate the same procedure on
Ubuntu 9.10. By manually editing the network connection (on NM), if I
select "No Security", the connection attempt fails as described in my
original post. 
If I select anything else (WPA, WEP,...), the GUI does not allow to
leave a blank password field. 
And there is no "Enable Roaming Mode" option to select or deselect.

Any ideas now?  :-)