Hi again,
For the record the problem is solved. After changing frequency on wifi, there was no interference. Then the connection was reestablished... but there was a problem with the service provider and I was without any access what so ever. So I called then and they checked and fixed the problem from their side. Now all is well.
All in all, it was a real learning experience.
The response from launchpad was fast and immediate. Something that is rare these days.
Also, from service provider...

Sincerely,

Hello again,
As an educator, I have always believed that knowledge is not a commodity that should be bought and sold(usually at high cost), but rather something that should be shared equally so that all may benifit.
That is what got me into open source and Linux. In that same spirit, I pass on the link to
my attempts to find a solution to my problem, with the help and support of the wonderful people in Launchpad. That way, everyone can follow and learn along with me. ( The brain is a muscle, and like all muscles must be exercised... or else it becomes weak and lazy.)
Fortunately, open source and Linux... allows me to exercise mine.

(https://answers.launchpad.net/ubuntu/+question/229010)

Sincerely,

Hi,
Thanks for reminding me.
I reported the problem on Launchpad.
Sincerely,

Hello again,
So far tried removing everything except the wifi client, nothing there.
Then just removed and reinstalled wifi client, nothing.
Finally reinstalled whole OS, nothing.
Even tried creating new account, changing frequencies, running a diagnostic test of modem.
As far as trying usb again... everytime it says that there is not enough space. Even though it is empty. Maybe, I'll just buy a larger one, they're cheap enough.(Mine is old)
It could just be too much interference... it has happened before. But it solved itself,after a while. I'm in Greece.... we have this problem with infrastructure. The government hasn't done much to improve ISP service, which results in wired and wireless problems.. since practically everybody has some wireless device... they're quite affordable.
That however is an economic/ political problem.
Thanks anyways for all the help. Will let you know if I do find a solution. For now, will use ethernet... like my son suggests anyways.
Sincerly,

Hi Izzy,

Thanks for replying. As far as I know, Ubuntu worked fine on Unity from the beginning.
The modem that I am using is a wireless adsl2+ T&W matr-X 4ew, at least that is what it says
on the manual. Other than Wifi Radar, I also use Windows wireless drivers and Broadcam STA
wireless driver. I updated them when reinstalling 12.04.
The whole problem started about 2 weeks ago, when spring break began. Then I begaan getting different signals on my wifi. There are many hot spots here, and almost everybody has an iphone or ipad.
Also, in an attempt to upgrade to 13.04 everything crashed because wubi isn't supported by 13.04 and I had to reinstall again on wubi. I'd like to try 13.04 first from a usb stick, but mine is too small and I'm looking for one compatable with linux that I can use for this. I have tried various tweeks that I have read on different forums. Nothing works.
If it helps... my laptop is a Samsung RF711. It has NVIDA Optimus , intel core i5. originally with windows 7. (here the problem started ) which is why I want to make a clean install.
I can't understand why wifi works with Windows and not with Ubuntu. Especially since it worked before.
I hope that this is enough information.
Sincerely,

Hi,
I have been using 12.04 happily since installing it. After a crash recently (from wubi) I reinstalled it with a usb stick. All works fine but suddenly, I can't use wifi. It recognizes the signal and shows that it is strong. But Wifi Radar also shows other signals. It just won't connect.
On Windows 7, however(which I also have for emergencies), all is well.
Is this an OS issue, am I missing something... that I also need to reinstall? Any commands that I could use? Or is it just that there is too much interference? (If so, why does it work with Windows?) Is there any way I could block these signals?
Also, I'd like to know which usb sticks are compatable with linux, and how many GB's are needed. I tried to load 13.04 on mine, 4GB and it wasn't eneough.
I know that these might sound like silly questions to those who are more experienced, but I would greatly appreciate any help. (My 60 yr. old brain is slow in learning )

Sincerely,

Hi,
I found this on another site and wanted to share it. A new market for Linux?

http://www.h-online.com/open/news/item/Ubuntu-Kylin-to-become-reference-OS-in-China-1829263.html

I recently discovered a different way to install Ubuntu desktops through the windows Ubuntu installer. It worked for the latest version... no need for iso disk or usb stick. Of course you must have Windows installed on your computer... below is the link.
(http://www.ubuntu.com/download/desktop/windows-installer)

Some may have already heard about this, but as usual I am late in learning.

Just a note.... my husband did something wrong and the whole system crashed and I had to reinstall it. Ubuntu 12.04. The nice thing is that once I got everything as it was, and installed Skype.... I tested it and everything worked... I don't know whether the problem was theirs or the OS, but whatever- a complete reinstall worked. Just be sure to save everything important.. on Ubuntu One or some other storage device.
Hope this helps. Someone once said that if all else fails, just start over from the beginning.

Thanks,
I tried all that, and no change. I can't help thinking that it's the test call app. that is the problem and that it might actually work. It happened before. I even ran commands in a terminal to test the microphone and it showed that it worked.