Cannot update UBUNTU 12.04.02 AMD64

[Gakhar]

Yes the lock problem is solved but i still can't download updates.
I am getting the same message "407 Proxy Authentication Required".

[varunendra]

I am getting the same message "407 Proxy Authentication Required".

Did you try what I suggested in my previous post ? -

.. as the error message suggests, please try a direct connection to avoid proxy authentication, or try changing the server (in Ubuntu Software Center > Edit > Software Sources) from "Pakistan" to "Main Server".

[Gakhar]

Already did but the problem remains. Why can't ubuntu update/install with internet via proxy. The firefox browser is working perfectly and i don't have any problem in surfing and downloading content.
I think it is related to some configuration file.

HELP. HELP. HELP or should i revert back to stupid windows.

[varunendra]

Why can't ubuntu update/install with internet via proxy.

Explained here : http://www.checkupdown.com/status/E407.html

Please check this out : http://askubuntu.com/questions/88976...ation-required

If you prefer to use the Synaptic way (I prefer it over Software Center anyway), but have problem in downloading it too (in apt-get install synaptic), you can use the following command to get the URI of the package(s) to be downloaded for synaptic:

apt-get install --print-uris synaptic

Then you can download them directly using your browser and install with dpkg -i * command.