Can you try opening a terminal (in the menu, Applications -> Accessories -> Terminal) and enter the following commands:

ifconfig -a

iwconfig

The output of

dmesg

lshw | grep -A12 '\-network'

I have exactly the same problem: WiFi works in Windows, ethernet cable works in Ubuntu (Hardy Heron), but WiFi doesn't work in Ubuntu. Since the original poster seems to have abandoned this thread, I'm taking over the position of n00b :huh:

When I boot up in Windows, the light that says "WIFI" usually comes on. But in Linux it doesn't come on even if I press the button, and if I go back to Windows I have to press the button to turn it on again.

The output from "dmesg" was 28K, so I've tried to attach it as a separate file, but I'm not sure if it's worked: [file name=dmesg_output.txt size=28714]http://www.linux.com/media/kunena/attachments/legacy/files/dmesg_output.txt[/file]

The output from the other 3 commands was as follows:

david@david-laptop:~$ ifconfig -a

eth0      Link encap:Ethernet  HWaddr 00:1d:60:ec:47:75  

          BROADCAST MULTICAST  MTU:1500  Metric:1

          RX packets:0 errors:0 dropped:0 overruns:0 frame:0

          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:1000 

          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

          Interrupt:20 Base address:0xdead 



lo        Link encap:Local Loopback  

          inet addr:127.0.0.1  Mask:255.0.0.0

          inet6 addr: ::1/128 Scope:Host

          UP LOOPBACK RUNNING  MTU:16436  Metric:1

          RX packets:2530 errors:0 dropped:0 overruns:0 frame:0

          TX packets:2530 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:0 

          RX bytes:126500 (123.5 KB)  TX bytes:126500 (123.5 KB)



david@david-laptop:~$ iwconfig

lo        no wireless extensions.

eth0      no wireless extensions.



david@david-laptop:~$ lshw | grep -A12 '-network'

WARNING: you should run this program as super-user.

137:        *-network DISABLED

138-             description: Ethernet interface

139-             product: 191 Gigabit Ethernet Adapter

140-             vendor: Silicon Integrated Systems [SiS]

141-             physical id: 4

142-             bus info: pci@0000:00:04.0

143-             logical name: eth0

144-             version: 02

145-             serial: 00:1d:60:ec:47:75

146-             width: 32 bits

147-             clock: 33MHz

148-             capabilities: bus_master cap_list ethernet physical

149-             configuration: broadcast=yes driver=sis190 driverversion=1.2 latency=0 module=sis190 multicast=yes

--

172:           *-network UNCLAIMED

173-                description: Ethernet controller

174-                product: AR242x 802.11abg Wireless PCI Express Adapter

175-                vendor: Atheros Communications Inc.

176-                physical id: 0

177-                bus info: pci@0000:02:00.0

178-                version: 01

179-                width: 64 bits

180-                clock: 33MHz

181-                capabilities: cap_list

182-                configuration: latency=0

183-        *-pci:2

184-             description: PCI bridge



david@david-laptop:~$ sudo lshw | grep -A12 '-network'

209:        *-network DISABLED

210-             description: Ethernet interface

211-             product: 191 Gigabit Ethernet Adapter

212-             vendor: Silicon Integrated Systems [SiS]

213-             physical id: 4

214-             bus info: pci@0000:00:04.0

215-             logical name: eth0

216-             version: 02

217-             serial: 00:1d:60:ec:47:75

218-             size: 10MB/s

219-             capacity: 100MB/s

220-             width: 32 bits

221-             clock: 33MHz

--

283:           *-network UNCLAIMED

284-                description: Ethernet controller

285-                product: AR242x 802.11abg Wireless PCI Express Adapter

286-                vendor: Atheros Communications Inc.

287-                physical id: 0

288-                bus info: pci@0000:02:00.0

289-                version: 01

290-                width: 64 bits

291-                clock: 33MHz

292-                capabilities: pm msi pciexpress msix cap_list

293-                configuration: latency=0

294-        *-pci:2

295-             description: PCI bridge

Maybe this helps:

http://www.ubuntuforums.org/showthread.php?t=339810&highlight=AR5212

Regards

OK, I looked at the other post. When I type "uname -r" it says "2.6.24-27-generic". I looked on Synaptic Package Manager. It lists a package named linux-restricted-modules-2.6.24-27-generic, and it says my installed version (of linux-restricted-modules-2.6.24-27-generic) is 2.6.24.18-27.5. This seems like a mixed message, to my untrained eyes. (Is the version number 2.6.24-27-generic or 2.6.24.18-27.5?) And there are also a few more versions installed:
- linux-restricted-modules-2.6.24-16-generic, version 2.6.24.12-16.34
- linux-restricted-modules-2.6.24-21-generic, version 2.6.24.14-21.51
- linux-restricted-modules-2.6.24-26-generic, version 2.6.24.18-26.3
- linux-restricted-modules-common, version 2.6.24.18-27.5
- linux-restricted-modules-generic, version 2.6.24.27.29
I tried following the link to the madwifi page, but the link was broken and their main page says they've delegated their software distribution to sourceforge, and I couldn't find madwifi-ng on sourceforge.
What do I do now?