Solve the problem that the wireless Nic cannot be enabled in Ubuntu

Solve the problem that the wireless Nic cannot be enabled in Ubuntu

Lspci is running properly and displays the atheros ar9285 wireless network adapter (pCI-Express)
No related error in dmesg
Ifconfig does not have wlan0, ifconfig-A displays wlan0
Iwconfig has wlan0
Iwlist can search for hot spots, but it cannot be connected anyway.
The nm-applet prompt on the desktop is not enabled
Rfkill is taken into consideration first, because the soft lock of rfkill is also the cause of Poor Nic configuration. The rfkill list shows that both the soft and hard locks are closed.
I thought it was a driver problem, but Google's result was that the atheros driver was provided since 2.6.x.
Then try to manually add wlan0 to/etc/Network/interfaces, as shown below:

# Wlan0
Auto wlan0
Iface wlan0 Inet DHCP

Still not good
Google once, someone posted a solution on the prayaya Forum:

First, download the driver here. ProgramPackage.
Http://linuxwireless.org/en/users/Download/stable/
Then, in the "terminal" of the "attachment", "cd" is included in the directory where the driver unzipping package is located, and then typed in sequence:
Make
Sudo make install
Sudo make unload
After completion, enter:
CD/etc
Sudo Pico modules
Select the abbreviation of your Nic module. Because I am using ar9285, I will enter:
Ath9k
After saving and exiting, restart your computer and pull everything!
This method is suitable for almost all wireless network adapters. The only difference is that you can change the module name to your own module name.

So I downloaded Linux-wireless and prepared for compilation.
P.s.: During the download, I found that all Linux kernel versions are 3.0, and I am still in the 2.6 era, and I feel a lot of pressure!
P. p.s.: In the past, Firefox had 5! Changing! But I like chrome and chromium more and more.
Due to the ever-changing changes, I upgraded the kernel to 2.6.38-11 before compiling, and then restarted. The result shows that the NM-applet prompts "the device is not hosted "! I have never seen this before! Decisively, Google saw a post on the UBUNTU Forum, which roughly meant that If/etc/Network/interfaces was modified, NetworkManager would not work by default.
Therefore, modify/etc/NetworkManager. conf and find
[Ifupdown]
Managed = false
Change
[Ifupdown]
Managed = true
Save and enter
Sudo/etc/init. d/networking restart
Restart the network service and change immediately!
P.s.: Some people said that installing backports can also solve the problem, which has not been confirmed.