The repository 'http://ppa.launchpad.net/gnome-terminator/ppa/ubuntu yakkety Release' does not have a Release file [duplicate]

  • Open Software & Updates, Other Software tab.
  • find the PPA definition that contains "gnome-terminator"
  • select it and click Edit
  • change the Distribution field from yakkety to xenial
  • save the changes
  • update the software database when prompted
  • problem solved

Source: http://ppa.launchpad.net/gnome-terminator/ppa/ubuntu/dists/