So I just installed Debian 9.0.0 on my PC and now I can't download packages with the Synaptic packet manager as the sources.list file under
/etc/apt/ has only the DVD set.
All other lines are commented out, with this text above the 2 lines I'd like to take back in:
# Line commented out by installer because it failed to verify:
This is probably due to the fact that I wasn't connected to the Internet while installing Debian using the DVD.
Also apparently the DVD isn't detected under Debian as under
/media/ it only says
cdrom0 no matter if I insert the DVD or not with both being empty. -> Not sure if that is a separate issue?
I cannot edit the sources.list file by just opening it with the texteditor as it's write-protected.
I thought about installing leafpad from here: https://packages.debian.org/stretch/amd64/leafpad/download and I'm not sure if that would help.
To me it seems that the most straight-forward way would be to open the texteditor as root, comment out the DVD sources and take the 2 security.debian.org sources back in. However I'm not sure how to do that.
sudo gedit which gets me this (I translated the part after
Unable to init server:):
No protocol specified Unable to init server: Connection failed:connection buildup denied (gedit:1297): Gtk-WARNING **: cannot open display: :0
I would greatly appreciate any help.