How can I delete encrypted files to recover HDD space?

Question

I tried to re-install Ubuntu 14.04 LTS and I unknowingly checked on the option of Encrypt the new Ubuntu installation for security. Unfortunately I stopped the installation at midway, and then began to install Ubuntu without the encryption option. Nonetheless I think some files managed to get encrypted because my hard drive partition is not reporting all the memory there is: this partition is 991 GB, but the system tells me its capacity is 975 GB and that 925.5 GB are free. This doesn't make sense!

I used an external HDD to backup my important stuff and I (slow) formatted the partition. I am currently running Ubuntu with a live USB, so I don't really care about my files. What I am trying to solve is to delete the suspected encrypted files, so I can recover about 65 GB of lost/encrypted space. I still remember the pass-phrase I created, but i have no clue of what to do next; I haven't really do any encryption/decryption before. I am also new to Ubuntu, so there are some technical things which I'm not very familiar with.

I am posting a picture about the properties of the hard drive (notice the suspicious gray area on the pie): hard drive space

I am really open to suggestions in any case or if the problem doesn't have anything to do with encrypted files. Thanks in advance.

Answer 1

You can probably do this with the Disks utility that comes with Ubuntu, but I find that installing GParted is much easier and more clear. Maybe I am partial to it, but it just seems more human readable to me.

Anyway, go to the Ubuntu Software application and install GParted. Once it finishes, run it. If you don't see it available to run, just reboot and look again. It asks for your password when you first start it up. This is normal, but be careful not to make changes to your filesystem unless you mean to.

Once in GParted, make sure you hard drive is selected in the upper right. It is usually /dev/sda or possibly /dev/sdb, or something similar. Look for the right hard drive size you have installed.

In the bottom part of this program you should now see any partitions that are listed on that drive. If you see anything that says crypt-luks or similar, it may be that encrypted partition you were talking about. It is normal to see one for /boot, one for /, sometimes one for /home, and there may be one that is marked as swap space. These are all normal.

If your previously encrypted volume doesn't show up here at all, but you notice some free space that should be used, then you should be able to resize your partition using this tool. Just make sure you boot from a live CD or USB first so you don't have to mess with unmounting or turning off the swap partition. It can get messy.

I personally would boot to the live CD/USB, kill ALL partitions on my target drive using GParted, then restart a fresh install using either full encryption or no encryption, whichever you prefer...and this time, let it finish. ;-)

Good luck!