The disk contains an unclean file system (0, 0). The file system wasn't safely closed on Windows. Fixing. The disk contains an unclean file system (0, 0). The file system wasn't safely closed on Windows. Fixing. mount: mounting /cow on /root/cow failed: No such file or directory passwd: password expiry information changed. dbus-daemon[955]: [session uid=999 pid=955] Activating service name='org.gtk.vfs.Daemon' requested by ':1.0' (uid=999 pid=956 comm="" label="unconfined") dbus-daemon[955]: [session uid=999 pid=955] Successfully activated service 'org.gtk.vfs.Daemon' dbus-daemon[955]: [session uid=999 pid=955] Activating service name='org.gtk.vfs.Metadata' requested by ':1.0' (uid=999 pid=956 comm="" label="unconfined") fuse: device not found, try 'modprobe fuse' first dbus-daemon[955]: [session uid=999 pid=955] Successfully activated service 'org.gtk.vfs.Metadata' A connection to the bus can't be made Using CD-ROM mount point /cdrom/ Identifying... [262d29a6a66e8f1bebc790a773ce80ec-2] Scanning disc for index files... Found 2 package indexes, 0 source indexes, 0 translation indexes and 1 signatures Found label 'Ubuntu 20.04 LTS _Focal Fossa_ - Release amd64 (20200423)' This disc is called: 'Ubuntu 20.04 LTS _Focal Fossa_ - Release amd64 (20200423)' Copying package lists...gpgv: Signature made Thu Apr 23 07:51:19 2020 UTC gpgv: using RSA key D94AA3F0EFE21092 gpgv: Good signature from "Ubuntu CD Image Automatic Signing Key (2012) " Reading Package Indexes... 0% Reading Package Indexes... Done Writing new source list Source list entries for this disc are: deb cdrom:[Ubuntu 20.04 LTS _Focal Fossa_ - Release amd64 (20200423)]/ focal main restricted Repeat this process for the rest of the CDs in your set.