[Ubuntu] There was a problem reading data from the CD-ROM. Please make sure it is in the drive. If retrying does not work, you should check the integrity of your CD-ROM. Failed to copy file from CD-ROM. Retry?

今天使用usb安裝 Ubuntu 14.04到Server一直失敗，且安裝過程一直出現這個錯誤訊息

There was a problem reading data from the CD-ROM. Please make sure it is in the drive. If retrying does not work, you should check the integrity of your CD-ROM.  Failed to copy file from CD-ROM. Retry?

後來發現是 unetbootin搞的鬼，不知道它中間做了什麼事？故只要改用linux dd即可解決該問題。

指令：

dd if=ubuntu-14.04-server-amd64.iso of=/dev/sdb bs=16M