I am trying to use dual-booting between Windows 7 and Ubuntu 14.04 I have Ubuntu on a USB with 8GB space, I have partitioned my hard-drive so that it has around 3gb space (as that is the maximum it will allow me to partition, even though I have a 1.7TB Hard Drive with over 1.5TB left), and it says No root file could be found? I do not know where to start, so I have not tried anything.
In this case, please shrink your hard disk on windows to create more space for ubuntu installation.
Login to windows and navigate to system management> disk management, then right click on the drive which has more space and shrink the drive. You can refer the below article for partioning a drive on windows: http://windows.microsoft.com/en-au/windows/repartition-hard-disk#1TC=windows-7
Shut-down your system then boot to Ubuntu live. On the installation type select "something else".
Then create a ext4 partition in the free space you made in windows and set it to "/" and "format"
Then set the 100mb "UEFI" partition (if you have one) to boot but don't format it.
Click next and it should continue installation.