I try to upgrade to the latest release of Ubuntu (14.04 - Alpha).
I typed this in the Terminal:
$ sudo update-manager -d
After some checks, a popup appeared:
I clicked the Upgrade... button:
Preparing to upgrade was successful, but Setting new sofware channels fails:
How can this be fixed?
Just disable the "extra" repositories. These packages still not have trusty counter part, since most of them are for Stable versions:
To disable the extras repositories, just remove all the extras entries from /etc/apt/sources.list file or use the software sources and untick the extras entries there.
sudo sed -i '/extras\.ubuntu\.com/d' /etc/apt/sources.list
extrasentries from/etc/apt/sources.listmust be removed to be able to upgrade. So, I believe that the close votes can be removed...