Package: cdrom-detect Version: 1.36 Downstream bug report: https://bugs.launchpad.net/ubuntu/+source/cdrom-detect/+bug/582427 Some usb-based installs are blocked due to cdrom-detect failing. I can't test 1.37 right now, but the changelog leads me to believe that this issue is likely not resolved there. The work-around is to add "cdrom-detect/try-usb=true" as a option on the kernel boot line