Fsck does not work

To run fsck on your harddrive you need to boot a liveCD and then run the commands with your harddrive partitions as the target.

"There is no /forcefsck file in my root"

-You need to create the file, it is just a blank file so run sudo touch /forcefsck and fsck will check your drive next time your reboot.

Finally found this link where file system type ext4 gets a bashing but after giving all the tips I'd already tried, it finally says do this:

sudo mkfs.ext4 -S /dev/sda1

This will replace all your superblocks with correct data, assuming the blocksize is guessed correctly (the default is correct for most systems.) If you need to use this, please read the man page on -S first. Don't blame me!

but only if you feel lucky.

It fixed the partition so I could read it again. However, I had to run fsck to fix the errors that were still there, and that dumped the content of /etc and a lot of other stuff into /lost+found so I'm going to have to do a re-install and restore from back-up to get it going again.