I was trying Ubuntu 16.04 but had issues and decided to install 14.04 over it. I have 16.04 installed on a single ext4 partition and encrypted my home folder (I remember the encryption passphrase).
Before installing 14.04 I created a 2nd ext4 partition on the same hard drive and made a copy of the files I need from my home folder. I later came across a post that suggested I could have installed 14.04 over 16.04 and kept my home folder (argh).
I thought I was installing over the first partition on my disk but I must have been paying full attention. I also installed LVM, which may have made things worse, in an attempt to prevent this in the future.
I booted to 14.04 and tried to a rescue with GParted but that didnt work. I installed testdisk and after a deep analysis I was able to find my previous root with my home folder and .ecryptfs files.
I think that I need to try to rebuild the ext4 file system, then mount it and decrypt and move the files where I need them. I need a little help getting there. I think I need to assign a file system from testdisk but I want to be sure. Also, does this have to be done from a Live CD? I realize once the files get written over I cant get them back.