Here's how you can upgrade Ubuntu Linux 12.04.1 LTS to 12.10.
1. Launch the Update Manager.
2. Click the Check button in Update Manager to see if there are updates available.
3. Click the Install Updates button.
4. Click the Check button again.
5. Click the Upgrade button.
6. The new release message will appear, click the Upgrade button to install Ubuntu 12.10.
For more, see the original article at the link below.