wlan0 No scan results -> Bus 001 Device 002: ID 0cf3:1002 Atheros Communications, Inc. -> TP-Link TL-WN821N wireless USB adapter not working in Ubuntu 10.04.1 LTS

I am unable to connect to a wireless network with a TP-Link TL-WN821N. Here are the results from the steps found on:
https://help.ubuntu.com/community/WirelessTroubleshootingProcedure

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ldconfig deferred processing now taking place
  *-network
       description: Ethernet interface
       product: RTL8111/8168B PCI Express Gigabit Ethernet controller
       vendor: Realtek Semiconductor Co., Ltd.
       physical id: 0
       bus info: pci@0000:02:00.0
       logical name: eth0
       version: 02
       serial: 00:30:48:b1:5e:4e
       size: 100MB/s
       capacity: 1GB/s
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress msix vpd bus_master cap_list rom ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=full ip=10.0.1.4 latency=0 link=yes multicast=yes port=MII speed=100MB/s
       resources: irq:27 ioport:d800(size=256) memory:feaff000-feafffff memory:fdef0000-fdefffff(prefetchable) memory:feac0000-feadffff(prefetchable)
  *-network
       description: Ethernet interface
       product: RTL8111/8168B PCI Express Gigabit Ethernet controller
       vendor: Realtek Semiconductor Co., Ltd.
       physical id: 0
       bus info: pci@0000:03:00.0
       logical name: eth1
       version: 02
       serial: 00:30:48:b1:5e:4f
       size: 10MB/s
       capacity: 1GB/s
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress msix vpd bus_master cap_list rom ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd 1000bt 1000bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=half latency=0 link=no multicast=yes port=MII speed=10MB/s
       resources: irq:28 ioport:e800(size=256) memory:febff000-febfffff memory:fdff0000-fdffffff(prefetchable) memory:febc0000-febdffff(prefetchable)
  *-network
       description: Wireless interface
       physical id: 1
       logical name: wlan0
       serial: d8:5d:4c:8a:d9:1c
       capabilities: ethernet physical wireless
       configuration: broadcast=yes multicast=yes wireless=IEEE 802.11bg
0: phy0: Wireless LAN
 Soft blocked: no
 Hard blocked: no
lo Interface doesn't support scanning.

eth0 Interface doesn't support scanning.

eth1 Interface doesn't support scanning.

wlan0 No scan results

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
auto wlan0
iface wlan0 inet dhcp
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=10.04
DISTRIB_CODENAME=lucid
DISTRIB_DESCRIPTION="Ubuntu 10.04.1 LTS"
00:00.0 Host bridge [0600]: Intel Corporation 82945G/GZ/P/PL Memory Controller Hub [8086:2770] (rev 02)
00:02.0 VGA compatible controller [0300]: Intel Corporation 82945G/GZ Integrated Graphics Controller [8086:2772] (rev 02)
00:1c.0 PCI bridge [0604]: Intel Corporation N10/ICH 7 Family PCI Express Port 1 [8086:27d0] (rev 01)
00:1c.4 PCI bridge [0604]: Intel Corporation 82801GR/GH/GHM (ICH7 Family) PCI Express Port 5 [8086:27e0] (rev 01)
00:1c.5 PCI bridge [0604]: Intel Corporation 82801GR/GH/GHM (ICH7 Family) PCI Express Port 6 [8086:27e2] (rev 01)
00:1d.0 USB Controller [0c03]: Intel Corporation N10/ICH7 Family USB UHCI Controller #1 [8086:27c8] (rev 01)
00:1d.1 USB Controller [0c03]: Intel Corporation N10/ICH 7 Family USB UHCI Controller #2 [8086:27c9] (rev 01)
00:1d.2 USB Controller [0c03]: Intel Corporation N10/ICH 7 Family USB UHCI Controller #3 [8086:27ca] (rev 01)
00:1d.3 USB Controller [0c03]: Intel Corporation N10/ICH 7 Family USB UHCI Controller #4 [8086:27cb] (rev 01)
00:1d.7 USB Controller [0c03]: Intel Corporation N10/ICH 7 Family USB2 EHCI Controller [8086:27cc] (rev 01)
00:1e.0 PCI bridge [0604]: Intel Corporation 82801 PCI Bridge [8086:244e] (rev e1)
00:1f.0 ISA bridge [0601]: Intel Corporation 82801GB/GR (ICH7 Family) LPC Interface Bridge [8086:27b8] (rev 01)
00:1f.1 IDE interface [0101]: Intel Corporation 82801G (ICH7 Family) IDE Controller [8086:27df] (rev 01)
00:1f.2 IDE interface [0101]: Intel Corporation N10/ICH7 Family SATA IDE Controller [8086:27c0] (rev 01)
00:1f.3 SMBus [0c05]: Intel Corporation N10/ICH 7 Family SMBus Controller [8086:27da] (rev 01)
02:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller [10ec:8168] (rev 02)
03:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller [10ec:8168] (rev 02)
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 003: ID 05c7:2022 Qtronix Corp.
Bus 002 Device 002: ID 05c7:7002 Qtronix Corp.
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 002: ID 0cf3:1002 Atheros Communications, Inc.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
H/W path Device Class Description
========================================================
                                  system X7SLM-L
/0 bus X7SLM-L
/0/0 memory 64KiB BIOS
/0/4 processor Intel(R) Celeron(R) CPU E150
/0/4/5 memory 64KiB L1 cache
/0/4/6 memory 512KiB L2 cache
/0/f memory 2GiB System Memory
/0/f/0 memory 1GiB DIMM SDRAM Synchronous
/0/f/1 memory DIMM [empty]
/0/f/2 memory 1GiB DIMM SDRAM Synchronous
/0/f/3 memory DIMM [empty]
/0/100 bridge 82945G/GZ/P/PL Memory Controller Hu
/0/100/2 display 82945G/GZ Integrated Graphics Contr
/0/100/1c bridge N10/ICH 7 Family PCI Express Port 1
/0/100/1c.4 bridge 82801GR/GH/GHM (ICH7 Family) PCI Ex
/0/100/1c.4/0 eth0 network RTL8111/8168B PCI Express Gigabit E
/0/100/1c.5 bridge 82801GR/GH/GHM (ICH7 Family) PCI Ex
/0/100/1c.5/0 eth1 network RTL8111/8168B PCI Express Gigabit E
/0/100/1d bus N10/ICH7 Family USB UHCI Controller
/0/100/1d.1 bus N10/ICH 7 Family USB UHCI Controlle
/0/100/1d.2 bus N10/ICH 7 Family USB UHCI Controlle
/0/100/1d.3 bus N10/ICH 7 Family USB UHCI Controlle
/0/100/1d.7 bus N10/ICH 7 Family USB2 EHCI Controll
/0/100/1e bridge 82801 PCI Bridge
/0/100/1f bridge 82801GB/GR (ICH7 Family) LPC Interf
/0/100/1f.1 storage 82801G (ICH7 Family) IDE Controller
/0/100/1f.2 scsi2 storage N10/ICH7 Family SATA IDE Controller
/0/100/1f.2/0.0.0 /dev/sda disk 1TB WDC WD10EARS-00M
/0/100/1f.2/0.0.0/1 /dev/sda1 volume 243MiB Linux filesystem partition
/0/100/1f.2/0.0.0/2 /dev/sda2 volume 931GiB Extended partition
/0/100/1f.2/0.0.0/2/5 /dev/sda5 volume 931GiB Linux LVM Physical Volume pa
/0/100/1f.3 bus N10/ICH 7 Family SMBus Controller
/1 wlan0 network Wireless interface
Linux ubuntu 2.6.32-27-server #49-Ubuntu SMP Thu Dec 2 02:05:21 UTC 2010 x86_64 GNU/Linux
[ 0.000000] AMI BIOS detected: BIOS may corrupt low RAM, working around it.
[ 0.000000] No NUMA configuration found
[ 0.000000] found SMP MP-table at [ffff8800000ff780] ff780
[ 0.000000] No AGP bridge found
[ 0.344773] ACPI: No dock devices found.
[ 0.357915] usbcore: registered new interface driver usbfs
[ 0.357928] usbcore: registered new interface driver hub
[ 0.357977] usbcore: registered new device driver usb
[ 0.358599] hpet0: 3 comparators, 64-bit 14.318180 MHz counter
[ 0.370045] Switching to clocksource tsc
[ 0.375876] pnp: PnP ACPI: found 13 devices
[ 0.412473] ehci_hcd 0000:00:1d.7: using broken periodic workaround
[ 0.439935] usb usb1: configuration #1 chosen from 1 choice
[ 0.439985] hub 1-0:1.0: USB hub found
[ 0.440410] usb usb2: configuration #1 chosen from 1 choice
[ 0.440443] hub 2-0:1.0: USB hub found
[ 0.440737] usb usb3: configuration #1 chosen from 1 choice
[ 0.440776] hub 3-0:1.0: USB hub found
[ 0.441094] usb usb4: configuration #1 chosen from 1 choice
[ 0.441128] hub 4-0:1.0: USB hub found
[ 0.441446] usb usb5: configuration #1 chosen from 1 choice
[ 0.441478] hub 5-0:1.0: USB hub found
[ 0.441600] PNP: No PS/2 controller found. Probing ports directly.
[ 0.445204] device-mapper: multipath: version 1.1.0 loaded
[ 0.445208] device-mapper: multipath round-robin: version 1.0.0 loaded
[ 0.447517] BIOS EDD facility v0.16 2004-Jun-25, 0 devices found
[ 0.733662] eth0: RTL8168c/8111c at 0xffffc9000033a000, 00:30:48:b1:5e:4e, XID 1c4000c0 IRQ 27
[ 0.737836] eth1: RTL8168c/8111c at 0xffffc90000358000, 00:30:48:b1:5e:4f, XID 1c4000c0 IRQ 28
[ 0.759970] usb 1-1: new high speed USB device using ehci_hcd and address 2
[ 0.923234] usb 1-1: configuration #1 chosen from 1 choice
[ 1.321126] usb 2-2: new full speed USB device using uhci_hcd and address 2
[ 1.492477] usb 2-2: configuration #1 chosen from 1 choice
[ 1.495380] hub 2-2:1.0: USB hub found
[ 1.781332] usb 2-2.3: new full speed USB device using uhci_hcd and address 3
[ 1.916453] usb 2-2.3: configuration #1 chosen from 1 choice
[ 6.579823] usbcore: registered new interface driver hiddev
[ 6.581603] lp: driver loaded but no devices found
[ 6.585675] input: Generic USB K/B Hub as /devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2.3/2-2.3:1.0/input/input3
[ 6.585842] generic-usb 0003:05C7:2022.0001: input,hidraw0: USB HID v1.00 Keyboard [Generic USB K/B Hub] on usb-0000:00:1d.0-2.3/input0
[ 6.601455] input: Generic USB K/B Hub as /devices/pci0000:00/0000:00:1d.0/usb2/2-2/2-2.3/2-2.3:1.1/input/input4
[ 6.601618] generic-usb 0003:05C7:2022.0002: input,hidraw1: USB HID v1.00 Device [Generic USB K/B Hub] on usb-0000:00:1d.0-2.3/input1
[ 6.601676] usbcore: registered new interface driver usbhid
[ 6.601679] usbhid: v2.6:USB HID core driver
[ 7.042766] w83627ehf: Found W83627DHG-P chip at 0x290
[ 7.250070] usb 1-1: reset high speed USB device using ehci_hcd and address 2
[ 7.719182] Console: switching to colour frame buffer device 160x64
[ 8.410080] usb 1-1: firmware: requesting ar9170.fw
[ 8.642934] ath: EEPROM regdomain: 0x809c
[ 8.642939] ath: EEPROM indicates we should expect a country code
[ 8.642943] ath: doing EEPROM country->regdmn map search
[ 8.642946] ath: country maps to regdmn code: 0x52
[ 8.642949] ath: Country alpha2 being used: CN
[ 8.642952] ath: Regpair used: 0x52
[ 8.698289] usb 1-1: Atheros AR9170 is registered as 'phy0'
[ 8.698326] usbcore: registered new interface driver ar9170usb
[ 10.053691] ADDRCONF(NETDEV_UP): wlan0: link is not ready
[ 10.090110] r8169: eth0: link up
[ 10.090128] r8169: eth0: link up
[ 10.096448] r8169: eth1: link down
[ 10.096790] ADDRCONF(NETDEV_UP): eth1: link is not ready
[ 20.260021] eth0: no IPv6 routers present
lo no wireless extensions.

eth0 no wireless extensions.

eth1 no wireless extensions.

wlan0 IEEE 802.11bg ESSID:off/any
          Mode:Managed Access Point: Not-Associated Tx-Power=20 dBm
          Retry long limit:7 RTS thr:off Fragment thr:off
          Encryption key:off
          Power Management:off

# which ath5k cannot recover. To prevent this condition, stop
blacklist ath_pci
blacklist eth1394
# replaced by p54pci
blacklist prism54
# replaced by b43 and ssb.
blacklist bcm43xx
blacklist twl4030_wdt
> hal.1: read hal dataprocess 1538: arguments to dbus_move_error() were incorrect, assertion "(dest) == NULL || !dbus_error_is_set ((dest))" failed in file dbus-errors.c line 278.
This is normally a bug in some application using the D-Bus library.
libhal.c 3483 : Error unsubscribing to signals, error=The name org.freedesktop.Hal was not provided by any .service files
23: PCI 200.0: 0200 Ethernet controller
  [Created at pci.318]
  Unique ID: rBUF.y8ZNEUW4Nn8
  Parent ID: QSNP.IPvPpT9j6v3
  SysFS ID: /devices/pci0000:00/0000:00:1c.4/0000:02:00.0
  SysFS BusID: 0000:02:00.0
  Hardware Class: network
  Model: "Realtek RTL8111/8168B PCI Express Gigabit Ethernet controller"
  Vendor: pci 0x10ec "Realtek Semiconductor Co., Ltd."
  Device: pci 0x8168 "RTL8111/8168B PCI Express Gigabit Ethernet controller"
  SubVendor: pci 0x15d9 "Super Micro Computer Inc"
  SubDevice: pci 0x8168
  Revision: 0x02
  Driver: "r8169"
  Driver Modules: "r8169"
  Device File: eth0
  I/O Ports: 0xd800-0xd8ff (rw)
  Memory Range: 0xfeaff000-0xfeafffff (rw,non-prefetchable)
  Memory Range: 0xfdef0000-0xfdefffff (rw,prefetchable)
  Memory Range: 0xfeac0000-0xfeadffff (ro,prefetchable,disabled)
  IRQ: 27 (1253 events)
  HW Address: 00:30:48:b1:5e:4e
  Link detected: yes
  Module Alias: "pci:v000010ECd00008168sv000015D9sd00008168bc02sc00i00"
  Driver Info #0:
    Driver Status: r8169 is active
    Driver Activation Cmd: "modprobe r8169"
  Config Status: cfg=new, avail=yes, need=no, active=unknown
  Attached to: #11 (PCI bridge)

24: PCI 300.0: 0200 Ethernet controller
  [Created at pci.318]
  Unique ID: JNkJ.y8ZNEUW4Nn8
  Parent ID: HnsE.KEovmcO7Ag4
  SysFS ID: /devices/pci0000:00/0000:00:1c.5/0000:03:00.0
  SysFS BusID: 0000:03:00.0
  Hardware Class: network
  Model: "Realtek RTL8111/8168B PCI Express Gigabit Ethernet controller"
  Vendor: pci 0x10ec "Realtek Semiconductor Co., Ltd."
  Device: pci 0x8168 "RTL8111/8168B PCI Express Gigabit Ethernet controller"
  SubVendor: pci 0x15d9 "Super Micro Computer Inc"
  SubDevice: pci 0x8168
  Revision: 0x02
  Driver: "r8169"
  Driver Modules: "r8169"
  Device File: eth1
  I/O Ports: 0xe800-0xe8ff (rw)
  Memory Range: 0xfebff000-0xfebfffff (rw,non-prefetchable)
  Memory Range: 0xfdff0000-0xfdffffff (rw,prefetchable)
  Memory Range: 0xfebc0000-0xfebdffff (ro,prefetchable,disabled)
  IRQ: 28 (no events)
  HW Address: 00:30:48:b1:5e:4f
  Link detected: no
  Module Alias: "pci:v000010ECd00008168sv000015D9sd00008168bc02sc00i00"
  Driver Info #0:
    Driver Status: r8169 is active
    Driver Activation Cmd: "modprobe r8169"
  Config Status: cfg=new, avail=yes, need=no, active=unknown
  Attached to: #12 (PCI bridge)

31: USB 00.0: 0282 WLAN controller
  [Created at usb.122]
  Unique ID: ADDn.QXmngvZJbA0
  Parent ID: k4bc.9T1GDCLyFd9
  SysFS ID: /devices/pci0000:00/0000:00:1d.7/usb1/1-1/1-1:1.0
  SysFS BusID: 1-1:1.0
  Hardware Class: network
  Model: "Atheros USB2.0 WLAN"
  Hotplug: USB
  Vendor: usb 0x0cf3 "Atheros Communications, Inc."
  Device: usb 0x1002 "USB2.0 WLAN"
  Revision: "1.06"
  Serial ID: "12345"
  Driver: "ar9170usb"
  Driver Modules: "ar9170usb"
  Device File: wlan0
  Features: WLAN
  Speed: 480 Mbps
  HW Address: d8:5d:4c:8a:d9:1c
  Link detected: no
  WLAN channels: 1 2 3 4 5 6 7 8 9 10 11 12 13
  WLAN frequencies: 2.412 2.417 2.422 2.427 2.432 2.437 2.442 2.447 2.452 2.457 2.462 2.467 2.472
  WLAN encryption modes: WEP40 WEP104 TKIP CCMP
  WLAN authentication modes: open sharedkey wpa-psk wpa-eap
  Module Alias: "usb:v0CF3p1002d0106dcFFdscFFdpFFicFFisc00ip00"
  Driver Info #0:
    Driver Status: ar9170usb is active
    Driver Activation Cmd: "modprobe ar9170usb"
  Config Status: cfg=new, avail=yes, need=no, active=unknown
  Attached to: #26 (Hub)

[main]
NetworkingEnabled=true
WirelessEnabled=true
WWANEnabled=true
Module Size Used by
joydev 11008 0
appletalk 32161 0
nfsd 304567 13
exportfs 4202 1 nfsd
nfs 310660 0
lockd 75079 2 nfsd,nfs
nfs_acl 2709 2 nfsd,nfs
auth_rpcgss 44484 2 nfsd,nfs
arc4 1473 2
fbcon 39270 71
tileblit 2487 1 fbcon
font 8053 1 fbcon
bitblit 5811 1 fbcon
softcursor 1565 1 bitblit
vga16fb 12757 0
vgastate 9857 1 vga16fb
i915 323478 1
ar9170usb 56494 0
drm_kms_helper 30742 1 i915
w83627ehf 23314 0
drm 198532 2 i915,drm_kms_helper
mac80211 238864 1 ar9170usb
hwmon_vid 3130 1 w83627ehf
led_class 3764 1 ar9170usb
i2c_algo_bit 6024 1 i915
coretemp 5505 0
ath 9723 1 ar9170usb
sunrpc 228063 12 nfsd,nfs,lockd,nfs_acl,auth_rpcgss
psmouse 64576 0
video 20623 1 i915
usbhid 41116 0
lp 9336 0
cfg80211 148725 3 ar9170usb,mac80211,ath
parport 37160 1 lp
serio_raw 4950 0
intel_agp 29287 2 i915
output 2503 1 video
hid 83440 1 usbhid
r8169 39714 0
mii 5237 1 r8169