My laptop Lenovo T400 lost its wireless connection and couldn't detect the available wireless networks, immediately after I moved my laptop from one desk to another. I am not sure if moving it physically is the reason, but occasionally it is followed by losing wireless connection and detection.
I tried the following ways that I know to restart the wireless network card but couldn't make it work:
# 1st way $ sudo ifdown wlan0 ifdown: interface wlan0 not configured $ sudo ifup wlan0 Ignoring unknown interface wlan0=wlan0. # 2nd way $ sudo ifconfig wlan0 down $ sudo ifconfig wlan0 up SIOCSIFFLAGS: Operation not possible due to RF-kill # 3rd way $ sudo /etc/init.d/networking restart * Reconfiguring network interfaces... [ OK ]
I was wondering
- what the above three ways mean and how they differ from each other?
- Am I using them wrongly in order to restart my wireless network card and make it work?
Thanks and regards!
P.S. I have both Gnome network manager and WICD installed on my Ubuntu 10.10. But I have exited WICD, and it does not help.
Update: I followed the link https://help.ubuntu.com/10.04/internet/C/troubleshooting-wireless.html. The following command
$sudo lshw -C network
says my wlan0 is "Disabled", although it can find the wireless device wlan0 and gives information about it, such as the product name, vendor, phisal id, bus info, and clock frequency etc, which might suggests the wireless card is in place.
In such case, the link asks me to "Check that the device is on”:
Many wireless network devices can be turned on or off. Check to see if there is a hardware switch, some devices can be switched off from Windows and may need to be turned back on from Windows.
As I did not switch from Windows, I was wondering how I now check if there is a hardware switch? How can I turn my wireless network device on? Thanks!