When I update, after some file downloads it shows the below errors. What should I do now?
W:Failed to fetch cdrom://Ubuntu 14.04.3 LTS _Trusty Tahr_ - Beta amd64 (20150805)/dists/trusty/main/binary-amd64/Packages Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs
, W:Failed to fetch cdrom://Ubuntu 14.04.3 LTS _Trusty Tahr_ - Beta amd64 (20150805)/dists/trusty/restricted/binary-amd64/Packages Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs
, W:Failed to fetch cdrom://Ubuntu 14.04.3 LTS _Trusty Tahr_ - Beta amd64 (20150805)/dists/trusty/main/binary-i386/Packages Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs
, W:Failed to fetch cdrom://Ubuntu 14.04.3 LTS _Trusty Tahr_ - Beta amd64 (20150805)/dists/trusty/restricted/binary-i386/Packages Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs
, E:Some index files failed to download. They have been ignored, or old ones used instead.