Ubuntu not installing after first boot

[filoo]

so last night, a friend helped me install ubuntu with a 2 tb usb drive that i have. i choose normal installation, download updates while installing ubuntu, and when the install starts, a bit after the 75% mark, it comes up as an error saying that the installer encountered an error copying files to the hard disk. .[Errno 5] input/output error.

[yancek]

Was there anything (data) on the disk before you began installing Ubuntu?
Did you create partitions before or during the install?
Which installation option did you use?