Hi...
Ubuntu 14.10 had reached EOL (End of Life) in July, so I'm guessing that the repositories for this release have already been shut down. Please see
here, here and the bottom post
here. If you wish to continue using this version, there may be archive repositories (like the ones mentioned in the last link) that you can substitute for the ones no longer active.
However, with no further security or software updates being released for 14.10, you may want to install either 14.04 or 15.10.
Regards...