This was several years ago, and I don't remember the specifics, but it just seems to me that if you didn't have the proper software, then the files you were working on wouldn't work (e.g. if you e-mailed home a document you shouldn't have).
I could be totally wrong on this, though.
An encrypted hard drive could become corrupted the same way as an unencrypted hard drive -- if a sector goes bad and becomes unreadable. Encrypted or not, you would lose just that one sector. The only time it would be worse with an encrypted drive is if the sector that goes bad happens to be the spot on the drive where the keys are stored.
So as I understand things, software FDE works by encrypting nearly all data on a hard-drive (except for some Boot-Sector files) while the data is "at rest".
That means that when your computer is off, everything on your HDD should be safe.
But when your computer is on (i.e. "data in motion"), all of the files and data on your HDD are fully accessible just like they would be on an un-encrypted HDD. And therefore, if you were working on a HDD with FDE, and you decided to e-mail a "Top Secret" document to yourself at home, then when you got home and checked your e-mail, that "Top Secret" document would fully accessible at all times just like if it were never encrypted at all.
Is that correct?
Now, to your point above, here is how I understand things...
1.) If you had a HDD with software FDE, and one of the "sectors" that held the encryption tables went bad, your entire HDD would be useless.
2.) If you had a HDD with hardware FDE, and the microchip that held the encryption tables went bad, your entire HDD would be useless (unless you could somehow replace that microchip).
I'm not sure how likely either of those scenarios would be, but I guess it still makes me apprehensive about using FDE on my entire life?! :eek:
If you can indeed back things up onto another HDD in either an un-encrypted form, OR you can make a backup that also uses FDE, but would be completely independent of what happens on the original HDD, then I suppose you'd be just as safe as if you weren't using FDE, but who knows?! :-/