No, it doesn't do any verification. Either the .iso file is corrupt ( check it with md5sum ) or your usb stick corrupted it after it was written. Test the iso and if that is ok, format and recreate the usb stick. If the iso is corrupt, then download it again.
** Changed in: ubiquity (Ubuntu) Status: Incomplete => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1306977 Title: Ubuntu 14.04 amd64 beta2 install fails with "[Errno 5] Input/output error" (full disk install from USB drive) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubiquity/+bug/1306977/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs