It looks like you are trying to replace the OS on an existing partition and the permissions are messed up somehow. Can you mount the partition and provide the output of ls -al /mnt/etc/default? You should be able to mount it with:
sudo -s mount -t ext4 /dev/sda1 /mnt Assuming the partition in question is number 1, otherwise you will need to change the number. ** Changed in: ubiquity (Ubuntu) Status: Confirmed => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1579454 Title: Ubuntu GNOME 16.04 installer crashes during either copying files or installing the system steps To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubiquity/+bug/1579454/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs