Please insert the disk ... in drive /cdrom/ - It IS there & can be read!

Open a terminal from Applications->Accessories->Terminal and type:

sudo gedit /etc/apt/sources.list

give your user password when requested, you don't see nothing when you type it, then press enter.

and if there are any row starting with:

deb cdrom:[

Please put a "#" at beginning of this line or completely remove the row.

Hope this helps

Alternatively simply edit the aforementioned /etc/apt/sources.list

I'm just a novice but I did notice that the source installation media ubuntu was expecting was different to the iso I created.

I had to use sudo vim /etc/apt/sources.list then locate the line starting with deb cdrom and change the name of the source to what is saved on the cd/dvd. If you're unsure of this try using another pc and text editor to read the file called "README.diskdefines" and it tells you in there.

You should notice there are quotes (") where the installation is expecting underscores and there's no date at the end of the iso volume.

Worked easily for me anyhow.

Hi

I have installed Ubuntu 7.10 and after that I am planning to install packages like git-core / cu
by using the following commands
sudo apt-get install git-core
sudo apt-get install cu
I am getting the following error:(as mentioned by other people) and the problem is not getting solved by the above solutions.

*********************************************************************
umesh@umesh-desktop:~$ sudo apt-get install git-core
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following extra packages will be installed:
  libdigest-sha1-perl liberror-perl
Suggested packages:
  git-arch git-cvs git-svn git-email git-daemon-run git-gui gitk gitweb cogito
Recommended packages:
  git-doc patch curl
The following NEW packages will be installed:
  git-core libdigest-sha1-perl liberror-perl
0 upgraded, 3 newly installed, 0 to remove and 0 not upgraded.
Need to get 0B/3671kB of archives.
After unpacking 7827kB of additional disk space will be used.
Do you want to continue [Y/n]? y
Media change: please insert the disc labeled
 'Ubuntu 7.10 _Gutsy Gibbon_ - Release i386 (20071017)'
in the drive '/cdrom/' and press enter
*********************************************************************
can you please help me in this?

Both the above solutions get the apt system to bypass the disc media. looks like. But I think, with the understanding I got from the above solutions, I might have a solution that gets apt to actually use the disc media.

sudo apt-cdrom add -r -d /home/MeCasa/ubuntu-9.10-dvd-i386

When you add the media to apt, make sure you use -r option which will prompt for a name, then add the name from the Readme discdefines... sort of. The apt-cdrom does not like quotations. This is what I used and it seems to be working; Ubuntu 9.10 _Karmic Koala_ - Release i386

That's exactly what apt-cdrom names it, but without the date stamp at the end.

To me, this is a bug. Either apt needs to use the date stamp or the apt-cdrom command shouldn't be naming it with a date stamp-whether that's an issue with the media or the command or what. Or maybe there's a good reason for it being this way.....

I've only used the update manger a few times since making this change, so not sure it's actually working. I'm not getting prompted for the CD each time, and I was before.

Be real, be sober.

Tag: Please insert the disk labeled:Ubuntu 9.10 _Karmic Koala_ - Release i386 (20091028.2)in drive /cdrom/

Reference: /etc/fstab, added the line, /directory_of_disc/ubuntu-9.10-dvd-i386.iso /home/MeCasa/ubuntu-9.10-dvd-i386 iso9660 ro,loop,auto 0 0
  saved/exited, then created the directory/mount point, mkdir /home/MeCasa/ubuntu-9.10-dvd-i386 and reboot or mount, sudo mount -a . Man apt-cdrom