There’s one standard document on HOWTO get Network Connect working on Ubuntu Linux. It’s mad scientist’s doc: http://mad-scientist.us/juniper.html . However, there are a few things not covered. I’ll assume that you’ve followed mad scientist’s excellent guide before going any further. Issue #1: 64-bit Ubuntu By default, when you install java on your 64-bit system, you get a 64-bit java. No surprise there, right? Well, Juniper’s tools don’t play nice with 64-bit java.