i just installed ubuntu 14 on my 1.0TB external hd. I only use 700GB for the installation and 20GB for swap. I thought the remaining 280GB will be available for me to store files from windows anytime i wish to do so. But when I logged into windows, it does not see the partition at all. I need the 280GB space back. So i need help on how to make my ubuntu to completely use up the 1.0TB or help on how to make windows see the 280GB space. Thank you.
Since you can't modify a mounted partition, and can't unmount the partition for the running system, the easiest way would be to boot from the Ubuntu install disk into a live system. From there, you can run
Just drag the end of the partition toward the beginning (from right to left), leaving space at the end.
Then, you can create a new partition in the unused space, either with gparted (change type to NTFS or FAT32), or you should be able to use Windows, if you want.
Click on the partition you wish to expand, then click the orange arrow to expand it. If another partition exists, you may need to delete it.
To reformat a partition for windows, right click the partition, then choose "Format", and use the NTFS file system.