DISCOVER on Kubuntu 16.04 Initialization Error

[SageReal]

I tried adding new repositories from the Discover app and it failed and started bringing an initialization error every time i try to start discover or other applications too. I'm a newbie so I don't know anything about Kubuntu. I searched for a solution and got some commands which have all failed to run and fix the problem. Any time I run one it brings up the Malformed entry 52 in list error. Below are some of the commands I've tried and errors I got. Please help.

gadgetboy@SageReal:~$ sudo touch /var/lib/dpkg/status
gadgetboy@SageReal:~$ sudo dpkg --configure -a
gadgetboy@SageReal:~$ sudo apt-get update
E: Malformed entry 52 in list file /etc/apt/sources.list (Component)
E: The list of sources could not be read.

gadgetboy@SageReal:~$ sudo rm /var/lib/apt/lists/* -vf
rm: cannot remove '/var/lib/apt/lists/partial': Is a directory

gadgetboy@SageReal:~$ sudo -H gedit /etc/apt/sources.list
[sudo] password for gadgetboy:
sudo: gedit: command not found

[Snowhog]

Close the konsole.

Click anywhere on the Desktop that doesn't contain anything.

Type: kdesudo kate /etc/apt/sources.list

Type your user password when prompted and press Enter.

The Kate text editor will launch and open the sources.list file for editing "as root" (required, as this is a root owned file).

If you want, copy the contents of the file and paste it in a reply to this thread so we can examine the malformed entry.

[SageReal]

deb cdrom:[Kubuntu 16.04 LTS _Xenial Xerus_ - Release amd64 (20160420.1)]/ xenial main multiverse restricted universe

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

## Major bug fix updates produced after the final release of the
## distribution.
deb http://archive.ubuntu.com/ubuntu xenial-updates main restricted
# deb-src http://ke.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://archive.ubuntu.com/ubuntu xenial universe
# deb-src http://ke.archive.ubuntu.com/ubuntu/ xenial universe
deb http://archive.ubuntu.com/ubuntu xenial-updates universe
# deb-src http://ke.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://archive.ubuntu.com/ubuntu xenial multiverse
# deb-src http://ke.archive.ubuntu.com/ubuntu/ xenial multiverse
deb http://archive.ubuntu.com/ubuntu xenial-updates multiverse
# deb-src http://ke.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://archive.ubuntu.com/ubuntu xenial-backports main restricted universe multiverse
# deb-src http://ke.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 http://archive.ubuntu.com/ubuntu xenial-security main restricted
# deb-src http://security.ubuntu.com/ubuntu xenial-security main restricted
deb http://archive.ubuntu.com/ubuntu xenial-security universe
# deb-src http://security.ubuntu.com/ubuntu xenial-security universe
deb http://archive.ubuntu.com/ubuntu xenial-security multiverse
deb-src http://archive.canonical.com/ubuntu xenial
# deb-src http://security.ubuntu.com/ubuntu xenial-security multiverse

that's the whole text. i copy pasted.

[jglen490]

It looks like line 52 is,

deb-src http://archive.canonical.com/ubuntu xenial

which is the next to last line. Try to place a # at the beginning of the line and save the file. You'll need to do this with sudo and a text editor. Use

kdesudo kate /etc/apt/sources.list

as Snowhog showed above. Save the file.

[SageReal]

Thanks. That solved the problem. Mucho gracias

[jglen490]

You're welcome! And welcome to Kubuntu.

[Snowhog]

deb-src http://archive.canonical.com/ubuntu xenial
# deb-src http://security.ubuntu.com/ubuntu xenial-security multiverse

And the problem with this entry (first line above) is that it's missing the component part (a Debian based sources.list entry is comprised of three 'parts':

The base
The distribution
The component

(See Directory Structure)

It would appear that you attempted to add this entry, but that was unnecessary as the very next line; the one that is commented (has a # in front of it) is the matching 'source files' entry to the third to last line:

deb http://archive.ubuntu.com/ubuntu xenial-security multiverse

If one plans or intends to build packages 'from source', deb-src entries would be uncommented; the # and space would be removed. If one has no interest in building packages 'from source', then a # should be at the beginning of each deb-src entry (as all the others in your sources.list have).

So, if you want your sources.list file to be completely syntactically 'correct', you can just delete the malformed entry (second to last line). Doing so, or commenting it as you did, both work to prevent the error.