connecting to wifi internet using TP-Link (TL-WN723N) usb adapter with Ubuntu 12.10

Question

I use TP-Link (TL-WN723N, ver:2.2) usb adapter to connect to a wifi internet using Windows 7. Its WEP encryption type network and using a security key i can connect to internet. But in Ubuntu 12.10 i can see the wifi network is available in the Network manager but every time i try to connect to it, it keeps asking for the security key over and over again. I am using the correct security key but it won't connect to the network !

Do i have to install the correct driver for it in Ubuntu? If it is how?

Its kind of confusing because the system shows that there is a wireless network available, configures the network as a WEP type so it seems like the adapter is working. But it wont connect to the internet.

The output of lspci

lspci
00:00.0 Host bridge: Intel Corporation 2nd Generation Core Processor Family DRAM Controller (rev 09)
00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor     Family Integrated Graphics Controller (rev 09)
00:16.0 Communication controller: Intel Corporation 6 Series/C200 Series Chipset Family MEI Controller #1 (rev 04)
00:1a.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #2 (rev 05)
00:1b.0 Audio device: Intel Corporation 6 Series/C200 Series Chipset Family High Definition Audio Controller (rev 05)
00:1c.0 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 1 (rev b5)
00:1c.3 PCI bridge: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 4 (rev b5)
00:1d.0 USB controller: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #1 (rev 05)
00:1f.0 ISA bridge: Intel Corporation H67 Express Chipset Family LPC Controller (rev 05)
00:1f.2 SATA controller: Intel Corporation 6 Series/C200 Series Chipset Family SATA AHCI Controller (rev 05)
00:1f.3 SMBus: Intel Corporation 6 Series/C200 Series Chipset Family SMBus Controller (rev 05)
02:00.0 Ethernet controller: Broadcom Corporation NetLink BCM57788 Gigabit Ethernet PCIe (rev 01)

and the output of lsusb

lsusb
Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 003: ID 0bda:8176 Realtek Semiconductor Corp. RTL8188CUS 802.11n WLAN Adapter
Bus 002 Device 004: ID 413c:2107 Dell Computer Corp. 
Bus 002 Device 005: ID 046d:c05a Logitech, Inc. Optical Mouse M90

Answer 1

Download RTL8188CUS for Linux from Realtek.com

Extract the downloaded archive by right clicking, then selecting Extract Here.

Blacklist the original mudule:

echo 'blacklist rtl8192cu' | sudo tee -a /etc/modprobe.d/blacklist.conf

... then reboot.

Build the new module:

cd RTL8188C_8192C_USB_linux_v3.4.4_4749.20121105
sudo bash ./install.sh

It will take a minute to complete, and should start working right away.

PS: Keep the downloaded files, because you'll need to redo the last step after every kernel update.