Cannot connect to WPA2 Personal wireless network

I think that my problem is related to yours. Since my re-installation of Ubuntu Karmic yesterday I cannot connect to my wireless network which is WPA encrypted too. An older installation with the same set of packages (even the version numbers are equal) worked quite nice. Thus I am a little bit surprised.

What we have in common is the wireless adapter. Maybe a problem with the driver?

  *-network
       description: Wireless interface
       product: PRO/Wireless 3945ABG [Golan] Network Connection
       vendor: Intel Corporation
       physical id: 0
       bus info: pci@0000:03:00.0
       logical name: wmaster0
       version: 02
       serial: 00:1b:77:a4:f3:b1
       width: 32 bits
       clock: 33MHz
       capabilities: pm msi pciexpress bus_master cap_list logical ethernet physical wireless
       configuration: broadcast=yes driver=iwl3945 latency=0 multicast=yes wireless=IEEE 802.11abg
       resources: irq:31 memory:edf00000-edf00fff

Just did the upgrade to Karmic. When trying to connect to a WPA2 Personal wireless network, which is hidden, it does not work. If I make the network not hidden, then it is OK.
HP Compaq nc8430
uname -a
Linux ahost 2.6.31-14-generic #48-Ubuntu SMP Fri Oct 16 14:04:26 UTC 2009 i686 GNU/Linux
lshw
           *-network
                description: Wireless interface
                product: PRO/Wireless 3945ABG [Golan] Network Connection
                vendor: Intel Corporation
                physical id: 0
                bus info: pci@0000:10:00.0
                logical name: wmaster0
                version: 02
                serial: 00:1b:77:16:32:ea
                width: 32 bits
                clock: 33MHz
                capabilities: bus_master cap_list logical ethernet physical wireless
                configuration: broadcast=yes driver=iwl3945 ip=192.168.1.4 latency=0 multicast=yes wireless=IEEE 802.11abg
                resources: irq:29 memory:f4000000-f4000fff

schlehmil:
Which packages did you check the versions on? I'm thinking this is either related to network-manager, wpasupplicant, or the kernel (but I'm no expert in networking). Did any of those three change?

McIvor:

I cannot say for sure but I have updated the old system right before I did the reinstallation.

Gergely:

The networks that I tried are not hidden.

Today I visited my parents. Their network is also encrypted with WPA but the password is much more shorter (only 8 characters long). Surprisingly the connection attempt with my laptop succeeded. Therefore I tried it with the same password at home and this time the connection was initiated without any problems. Furthermore I tried it with WPA2 and my old password (20 characters long) and this works too. To summarize:

long password + WPA-Personal -> fail
short password + WPA-Personal -> success
long password + WPA2-Personal -> success
short password + WPA2-Personal -> success

So a successful login attempt appears to fix it for you? Interesting.
I'll try changing the password on my network tomorrow and see if it helps.

No it does not fix it. But a shorter password or switching to WPA2 will. I know that you have these issues with WPA2 so maybe it is not related to the length of the password but to the characters in the password?

Have the same problem in 10.04. Network manager can't connect to WPA2 network with passkey.
In 9.04 it was possible to connect with wicd, so I tried to use it instead of default netman. Result the same, but more interesting (see screenshot). Looks like near me exists another wlan with hidden ssid, but with 4-letters name (my has 6 letters in ssid). And then I am trying to connect it connects to other wlan with my pass... As a result I receive "ERROR: Bad password".
May be it can help to locate the problem...

OK, just to add fuel to the fire here...
I went on vacation for a couple weeks and used an unsecured wifi hotspot while I was gone. When I got home, I updated to the 2.6.32-24 kernel. The computer connected to my home network (WPA2) once. After suspending it overnight, it refused to connect again. So I figure it's got to be one of three things:
1. Ubuntu successfully makes a connection, but doesn't close it properly leaving something stuck in a loop (hinted at in the changelog for the kernel, but one would think this would be fixed by rebooting)
2. Before I left, I accidentally plugged an AC adapter into the microphone port (don't ask) and pumped 9V through the computer, frying the sound card. This may have jump-started the wireless card, the effect wearing off after time (since it works in Windows, I'm ruling out hardware failure)
3. Between the AC adapter and leaving for vacation, I took apart the laptop to try and get to the sound card. There may be a loose connection in the wireless adapter (again, I don't believe it's a hardware issue since it works fine in Windows and on other encryption schemes)
I'm going to try running another distribution just to check if it works there. If it does, I'll compare version numbers.

Thank you for taking the time to report this bug and helping to make Ubuntu better. We are sorry that we do not always have the capacity to look at all reported bugs in a timely manner. There have been many changes in Ubuntu since that time you reported the bug and your problem may have been fixed with some of the updates. It would help us a lot if you could test it on a currently supported Ubuntu version. When you test it and it is still an issue, kindly upload the updated logs by running apport-collect 459871 and any other logs that are relevant for this particular issue.

[Expired for network-manager (Ubuntu) because there has been no activity for 60 days.]