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I'm on Ubuntu 12.04 LTS (Precise). I can not upgrade to 12.10 using the Update manager. Each time I try, it shows that 12.10 is available to upgrade:

12.10 is available

However, when I click on "Upgrade", I get the following error:

Unable to load page
Problem occurred while loading the URL:
Cannot resolve proxy hostname()

Screenshot for same:

cannot resolve proxy hostname

It is not a problem with my internet because all of the normal updates for 12.04 work. It is just that I cannot upgrade to 12.10. How do I resolve this?

share|improve this question
Are you running behind a firewall and use a proxy server to connect? It is possible that the upgrade manager cannot connect via the proxy. There should be a setting for it somewhere. – kapad Mar 6 '14 at 10:13
up vote 1 down vote accepted

It is possible that you are not able to connect to the update mirror that you have chosen.

Try changing the mirror to the main site.

Go to System settings

Select Software & Updates Select Software & Updates

desc Select main server in the Download From drop down menu.

share|improve this answer
I changed the mirror from main site to US Mirror and it worked. Thanks a lot! :) – Gaurav Shirodkar Mar 6 '14 at 19:30
@GauravShirodkar - Mark this answer as correct. It will help people with the same problem find the solution faster. – kapad Mar 8 '14 at 23:55
srry i will do that right now... im still a n00b – Gaurav Shirodkar Mar 10 '14 at 1:41

Just out of curiosity why are you trying to upgrade to 12.10? Ubuntu 12.10 is coming to an EOL which means End Of Life and it's gonna be during April 2014.

My advice to wait for other LTS to be released that is 14.04 LTS Trusty Tahr which is scheduled to be released in April 2014. Then you can upgrade your current LTS release to a new LTS release what is Trusty Tahr.

To upgrade current release run sudo do-release-upgrade or insert your Ubuntu LiveCD and choose upgrade to the next LTS release.

more tutorial for LTS releases:

  1. Start System/Administration/Software Sources
  2. On the Updates tab, set Show new distribution releases: to Long term support releases only, then press Close.
  3. Press Alt-F2 and type update-manager -d
  4. Click the Check button to check for new updates. If there are any updates to install, use the Install Updates button to install them, and press Check again after that is complete.
  5. A message will appear informing you of the availability of the new release. Click Upgrade. Follow the on-screen instructions.

Also if you'd like to be notified about new LTS release run:

sudo gedit /etc/apt/sources.list

navigate to Updates tab and at the bottom make sure is set to notify me about new LTS release and you'll be notified when it's released.

share|improve this answer
Ok I will just wait a month until trusty tahr But can I go directly from LTS to LTS??? – Gaurav Shirodkar Mar 5 '14 at 0:26
yes you do! That's what I wrote my answer about it explains why and how and to add it's just doesn't make sense to upgrade now if you're still on 12.04 LTS just in a month you'll be able to jump to the new LTS. If my answer suits you don't forget to accept it if you agree. – JoKeR Mar 5 '14 at 13:39

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