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I just installed ubuntu 11.10, and tried to have it connect to the internet.

I use a wireless USB stick by edimax (it is called IEEE802.11b/g/n nano USB adapter or also EW-7811Un).

My problem is that Ubuntu seems to be able to use the USB to see the networks around me, but when I try to connect to my network - it just keeps trying and failing.

I am connected to the internet through a

300M Wireless N Router Model No. TL-WR841N / TL-WR841ND

Can you please advise on how this can be resolved?


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you have to turn off the power managment settings so the wireless dongle (wireless usb antennae) can get sufficent power to operate properly!

To do this temporarly you need to go to the terminal, which you you can press ctrl + alt + t to open it easily.

Then type sudo iwconfig wlan0 power off

This means is you enter the configuration settings for the wlan0 wifi number 0 (primary wifi access port) and power off means the power management setting for it will be turned off.

To check that it is indeed off after doing this command into the terminal type sudo iwconfig

It should pop up a bunch of stuff about your wifi settings and one of the lines should say power management: off

Your wifi should work properly for now. however this is not a permanent fix and you have to do this everytime you boot up your computer. there is a permanent fix but it involves hopping through hoops and im not entirely sure what is expected of me.

So basically its the power management that is choking your dongle from working efficently.

To turn off the power management (until the next time you boot up) open terminal (ctrl-alt-t again) and type sudo iwconfig wlan0 power off

You will be prompted to enter your password. Your internet should now work for this session.

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iwconfig is an obsolete tool. iw should be used instead: iw dev wlan0 set power_save pff – BatchyX May 25 '13 at 14:07

Here the list of Ubuntu Edimax suported Wireless Network cards: EW-7811 is listed there but you may try this option:

When the card is not (well) supported you have to use the Windows drivers to use it with NDISWrapper:

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