This looks like a regression since the 1024D keys were dropped from ubuntu-keyring.
Will make sure that only 4k key is used to sign the image. Oct 31 11:42:01 xubuntu ubiquity: /usr/lib/ubiquity/apt-setup/generators/01setup: 9: /usr/lib/ubiquity/apt-setup/generators/01setup: Oct 31 11:42:01 xubuntu ubiquity: cannot open /target/etc/apt/sources.list: No such file Oct 31 11:42:01 xubuntu ubiquity: Oct 31 11:42:02 xubuntu in-target: Reading package lists... Oct 31 11:42:02 xubuntu in-target: Oct 31 11:42:02 xubuntu apt-setup: Using CD-ROM mount point /cdrom/ Oct 31 11:42:02 xubuntu apt-setup: Identifying... [157a22de949d85c1b00a775fec8e721d-2] Oct 31 11:42:02 xubuntu apt-setup: Scanning disc for index files... Oct 31 11:42:02 xubuntu apt-setup: Found 8 package indices, 0 source indices, 0 translation indices and 1 signatures Oct 31 11:42:02 xubuntu apt-setup: Found label: Xubuntu 17.04 _Zesty Zapus_ - Alpha amd64 (20161031) Oct 31 11:42:02 xubuntu apt-setup: This disc is called: Oct 31 11:42:02 xubuntu apt-setup: 'Xubuntu 17.04 _Zesty Zapus_ - Alpha amd64 (20161031)' Oct 31 11:42:02 xubuntu apt-setup: Copying package lists... Oct 31 11:42:02 xubuntu apt-setup: gpgv: Signature made Mon 31 Oct 2016 02:16:38 GMT Oct 31 11:42:02 xubuntu apt-setup: Oct 31 11:42:02 xubuntu apt-setup: gpgv: using DSA key Oct 31 11:42:02 xubuntu apt-setup: Oct 31 11:42:02 xubuntu apt-setup: gpgv: Can't check signature: No public key Oct 31 11:42:02 xubuntu apt-setup: Oct 31 11:42:02 xubuntu apt-setup: Sub-process apt-key returned an error code (2) Oct 31 11:42:02 xubuntu apt-setup: #015Reading Package Indexes... 0% Oct 31 11:42:02 xubuntu apt-setup: #015Reading Package Indexes... Error! Oct 31 11:42:02 xubuntu apt-setup: Writing new source list Oct 31 11:42:02 xubuntu apt-setup: Source list entries for this disc are: Oct 31 11:42:02 xubuntu apt-setup: deb cdrom:[Xubuntu 17.04 _Zesty Zapus_ - Alpha amd64 (20161031)]/ zesty main multiverse restricted universe Oct 31 11:42:02 xubuntu apt-setup: Repeat this process for the rest of the CDs in your set. Oct 31 11:42:02 xubuntu apt-setup: E: Sub-process gpgv returned an error code (2) Oct 31 11:42:02 xubuntu apt-setup: W: Signature verification failed for: /cdrom/dists/zesty/Release.gpg ** Also affects: ubuntu-cdimage Importance: Undecided Status: New ** Changed in: ubuntu-cdimage Assignee: (unassigned) => Dimitri John Ledkov (xnox) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1637985 Title: Install Fail - Attempt to configure apt to install additional packages from CD To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-cdimage/+bug/1637985/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs