[ubuntu] Synaptic repositories issue

Code:

# deb cdrom:[Ubuntu 16.04 LTS _Xenial Xerus_ - Beta amd64 (20160323)]/ xenial main restricted

# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://ca.archive.ubuntu.com/ubuntu/ xenial main restricted
# deb-src http://ca.archive.ubuntu.com/ubuntu/ xenial main restricted

## Major bug fix updates produced after the final release of the
## distribution.
deb http://ca.archive.ubuntu.com/ubuntu/ xenial-updates main restricted
# deb-src http://ca.archive.ubuntu.com/ubuntu/ xenial-updates main restricted

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## universe WILL NOT receive any review or updates from the Ubuntu security
## team.
deb http://ca.archive.ubuntu.com/ubuntu/ xenial universe
# deb-src http://ca.archive.ubuntu.com/ubuntu/ xenial universe
deb http://ca.archive.ubuntu.com/ubuntu/ xenial-updates universe
# deb-src http://ca.archive.ubuntu.com/ubuntu/ xenial-updates universe

## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu 
## team, and may not be under a free licence. Please satisfy yourself as to 
## your rights to use the software. Also, please note that software in 
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://ca.archive.ubuntu.com/ubuntu/ xenial multiverse
# deb-src http://ca.archive.ubuntu.com/ubuntu/ xenial multiverse
deb http://ca.archive.ubuntu.com/ubuntu/ xenial-updates multiverse
# deb-src http://ca.archive.ubuntu.com/ubuntu/ xenial-updates multiverse

## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
deb http://ca.archive.ubuntu.com/ubuntu/ xenial-backports main restricted universe multiverse
# deb-src http://ca.archive.ubuntu.com/ubuntu/ xenial-backports main restricted universe multiverse

## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
deb http://archive.canonical.com/ubuntu xenial partner
# deb-src http://archive.canonical.com/ubuntu xenial partner

deb http://security.ubuntu.com/ubuntu xenial-security main restricted
# deb-src http://security.ubuntu.com/ubuntu xenial-security main restricted
deb http://security.ubuntu.com/ubuntu xenial-security universe
# deb-src http://security.ubuntu.com/ubuntu xenial-security universe
deb http://security.ubuntu.com/ubuntu xenial-security multiverse
# deb-src http://security.ubuntu.com/ubuntu xenial-security multiverse
deb http://ppa.launchpad.net/darklin20/bomi/ubuntu vivid main
# deb-src http://ppa.launchpad.net/darklin20/bomi/ubuntu vivid main[/QUOTE]

[QUOTE]gpgv:/var/lib/apt/lists/dl.google.com_linux_chrome_deb_dists_stable_Release.gpg: The repository is insufficiently signed by key 4CCA1EAF950CEE4AB83976DCA040830F7FAC5991 (weak digest)gpgv:/var/lib/apt/lists/ppa.launchpad.net_darklin20_bomi_ubuntu_dists_vivid_Release.gpg: The repository is insufficiently signed by key CBBE8C99E1693CC49F66BA5CC0FD17E37F15F99A (weak digest)The repository 'http://ppa.launchpad.net/kilian/f.lux/ubuntu vivid Release' does not have a Release file.Data from such a repository can't be authenticated and is therefore potentially dangerous to use.See apt-secure(8) manpage for repository creation and user configuration details.Failed to fetch http://ppa.launchpad.net/kilian/f.lu...amd64/Packages  404  Not FoundFailed to fetch http://ppa.launchpad.net/kilian/f.lu...-i386/Packages  404  Not FoundSome index files failed to download. They have been ignored, or old ones used instead.