no release file and error 404

[Joel Van Boxtel]

when I update from the main servers the following errors occur:
err: http://ppa.launchpad.net/artfwo/ppa/ubuntu Release
  404 Not Found

E: The repository 'http://ppa.launchpad.net/artfwo/ppa/ubuntu zesty Release'
  does not have a Release file.

 also
E: The repository 'http://ppa.launchpad.net/artfwo/ppa/ubuntu zesty Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.

sudo apt-cache policy pkgname
N: Unable to locate package pkgname

system info:
Description: Ubuntu Artful Aardvark (development branch)
Release: 17.10

what i expected:
404 error:
- that it will update from all servers available, due to that I connected to the server in a browser

does not have a release file
- idk

pkgname error:
- it should have one

what happen instead: look at top of document

ProblemType: Bug
DistroRelease: Ubuntu 17.10
Package: xfce4-terminal 0.8.6-0ubuntu1
ProcVersionSignature: Ubuntu 4.12.0-12.13-generic 4.12.8
Uname: Linux 4.12.0-12-generic i686
ApportVersion: 2.20.6-0ubuntu7
Architecture: i386
CurrentDesktop: XFCE
Date: Mon Aug 28 00:35:08 2017
ExecutablePath: /usr/bin/xfce4-terminal
InstallationDate: Installed on 2017-08-19 (8 days ago)
InstallationMedia: Xubuntu 16.04.3 LTS "Xenial Xerus" - Release i386 (20170801)
ProcEnviron:
 LANGUAGE=en_AU:en
 PATH=(custom, user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_AU.UTF-8
 SHELL=/bin/bash
SourcePackage: xfce4-terminal
UpgradeStatus: Upgraded to artful on 2017-08-26 (1 days ago)

[Unit 193 (unit193)]

Howdy,

You were getting that error due to a PPA not being published for the release you were on. This isn't from Ubuntu or Xubuntu, xfce4-terminal, or anything we control. You may wish to contact the ~artfwo user in regards to whatever PPA issues, if you still have said issues.