Using apt-get
Edit your /etc/apt/sources.list as root. Change every occurrence of dapper to edgy.
Use any prefered editor. If you have a CD-ROM line in your file, then remove it.
sudo vi /etc/apt/sources.list
or
use the following Simple command
sudo sed -e ’s/\sdapper/ edgy/g’ -i /etc/apt/sources.list
Now you need to update the source list using the following command
sudo apt-get update
Upgrade using the following command
sudo apt-get dist-upgrade
Double check your process was finished properly using the following commd
sudo apt-get -f install
sudo dpkg –configure -a
Now you need to Reboot your machine to take your new ubuntu 6.10 installation to effect all changes.
Have great fun with your new Ubuntu Edgy Eft
Other useful links:
http://www.ubuntuforums.org/showthread.php?t=227052
http://ubuntuforums.org/showthread.php?t=285304
http://www.debianadmin.com/ubuntu-edgy-upgrade-common-problems-with-solutions.html
http://www.desktoplinux.com/news/NS3291004537.html