connected to wifi but can't access internet

[K12963]

I have a wee Acer netbook running Xubuntu 14.04. Wifi claims to be connected and at full strength. I attempted with Chromium and Firefox, but they wouldn't connect to the internet. I can't download anything from Ubuntu Software Center either. I have an iPhone, another Xubuntu machine, and a Windows machine all of which work fine with the wifi. The problem machine has previously connected to different wifi without a hitch. I am very new to Linux, so please be gentle!

[Hadaka]

Hi,With a wred working connection please open a terminal and then
COPY and paste this..

 wget -N -t 5 -T 10 http://dl.dropbox.com/u/57264241/wireless_script && chmod +x wireless_script && ./wireless_script

this creates a wireless-info-text file in your home directory,post that file here so you may be helped.
more info on this process..please read.

http://ubuntuforums.org/showthread.php?t=370108&

thanks.

[K12963]

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