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I've had Ubuntu 10.10 on my server since I bought it several years back. I've tried to upgrade in the past but I'm always thwarted by my company's firewall. I receive messages like these:
W:Failed to fetch http://security.ubuntu.co/ubuntu/dists/natty-security/main/source/Sources.gz 407 Proxy Authentication Required (Forefront TMG requires authorization to fulfill the request. Access to the Web Proxy filter is denied. )
I have my System > Preferences > Network Proxy > HTTP proxy set appropriately (to use Port 80 to get through our firewall.) But still no luck.
I'm looking to upgrade from Ruby 1.8.7 to 1.9.3 and I'm really hesitant to install RVM until I've gotten this Ubuntu upgrade successfully completed. Can anyone suggest what I might be doing wrong / need to change?