unwanted sign in sources.list

[Frank]

there is always a unwanted sign (it seems) in sources.list, whenever i try to install. even if i remove the source that is causing the problem, it's there again after install and the installer is crashing then.

i didn't modified the sources list myself in any way, the "wrong" sign is always appearing there, no matter if in ubuntu, kubuntu, ubuntustudio or mint. so far i didn't found any way to install linux because that. i tried two with USB sticks, downloaded the images again, but because the error / installer crash i can't install linux at all.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: ubiquity 2.21.63
ProcVersionSignature: Ubuntu 4.4.0-21.37-lowlatency 4.4.6
Uname: Linux 4.4.0-21-lowlatency x86_64
ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
CasperVersion: 1.376
Date: Tue Aug 16 21:46:10 2016
InstallCmdLine: BOOT_IMAGE=/casper/vmlinuz file=/cdrom/preseed/ubuntustudio.seed boot=casper quiet splash ---
LiveMediaBuild: Ubuntu-Studio 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
ProcEnviron:
 LANGUAGE=de_DE.UTF-8
 PATH=(custom, no user)
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)

[Phillip Susi (psusi)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. Unfortunately, we cannot work on this bug because your description didn't include enough information. You may find it helpful to read "How to report bugs effectively" http://www.chiark.greenend.org.uk/~sgtatham/bugs.html. We'd be grateful if you would then provide a more complete description of the problem.

We have instructions on debugging some types of problems at http://wiki.ubuntu.com/DebuggingProcedures.

At a minimum, we need:
1. The specific steps or actions you took that caused you to encounter the problem.
2. The behavior you expected.
3. The behavior you actually encountered (in as much detail as possible).
Thanks!

[Launchpad Janitor (janitor)]

[Expired for ubiquity (Ubuntu) because there has been no activity for 60 days.]