I encountered this with Ubuntu 10.04 (Lucid Lynx) x86_64. DansGuardian is installed in whitelist mode but no exclusion for loopback IP addresses. Firefox set to use system proxy settings. DansGuardian blocked a connection from Firefox to 127.0.0.1 which should have been excluded from proxy. In gnome-network-properties (Network Proxy Preferences) the exclusions are:
localhost
127.0.0.0/8
*.local
Problem was resolved when 127.0.0.1 was added to the list.
I encountered this with Ubuntu 10.04 (Lucid Lynx) x86_64. DansGuardian is installed in whitelist mode but no exclusion for loopback IP addresses. Firefox set to use system proxy settings. DansGuardian blocked a connection from Firefox to 127.0.0.1 which should have been excluded from proxy. In gnome-network- properties (Network Proxy Preferences) the exclusions are:
localhost
127.0.0.0/8
*.local
Problem was resolved when 127.0.0.1 was added to the list.