Please run the memtest option from the boot menu for at least 15 minutes and let us know if it finds any errors. Also it appears that your /dev/sda had previously been used in a fakeraid and still has the now damaged signatures on it. You should use the dmraid utility to remove them.
** Changed in: ubiquity (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1786266 Title: Error on installing Ubuntu 18.04 from USB stick To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubiquity/+bug/1786266/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs