Proxy configuration in Kubuntu

Open up the terminal so we can edit a couple of files. Kate is just a text editor, use whatever you like, gedit, vim, whatever. This command will open apt.conf file in Kate as root.

$ sudo kate /etc/apt/apt.conf

Comment # out what is already there and add your proxy. Should look like below with your auth info:

#Acquire { http { Proxy 'false'; }; };
Acquire::http::Proxy "http://usern: passwd@proxy.domain.com:port_num";