Media change: please insert the disc labeled ‘Ubuntu 9.10 _Karmic Koala_ – Release i386 (20091028.5)’ in the drive ‘/cdrom/’ and press enter--The weird problem in ubuntu

When almost all the packages are downloaded, i saw the following lines from the terminal

Media change: please insert the disc labeled
‘Ubuntu 9.10 _Karmic Koala_ – Release i386 (20091028.5)’
in the drive ‘/cdrom/’ and press enter

the solution is..................

fire the terminal type the following commands in screenshot...

sources.list file looks as follows , comment the cdrom line in sources.list file

# deb cdrom:[Ubuntu 9.10 _Karmic Koala_ - Release i386 (20091028.2)]/ karmic main restricted
# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.

#deb cdrom:[Ubuntu 9.10 _Karmic Koala_ - Release i386 (20091028.5)]/ karmic main restricted #commented line
deb http://in.archive.ubuntu.com/ubuntu/ karmic main restricted
deb-src http://in.archive.ubuntu.com/ubuntu/ karmic main restricted

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

…………………………………………………………………….
……………………………………………………………………

  save & close the file

  apt-get update.

this is the solution to this weird problem.............