Set the proxy in "Network Proxy" setings and click "apply system-wide", and also at the following locations. Some terminal applications need them. sudo gedit /etc/apt/apt.conf.d/95proxies Acquire::http::proxy "http://username:passwd@proxy:port/"; Acquire::ftp::proxy "ftp://username:passwd@proxy:port/"; Acquire::https::proxy "https://username:passwd@proxy:port/"; sudo gedit .bashrc export http_proxy=http://username:passwd@proxy:port export https_proxy=http://username:passwd@proxy:port export HTTP_PROXY=http://username:passwd@proxy:port export HTTPS_PROXY=http://username:passwd@proxy:port Requires both CAPITALS and small ones. Some applications accepts only CAPITALS.