Windows 7: Full disk encryption isn't quite dead.

At least once a month, it seems some vendor or techie claims to have broken a version of a hard drive full-disk encryption (FDE) program scheme, whether it's from Microsoft (my full-time employer), BitLocker, open source favorite TrueCrypt, or some other variant. All the stories and the hype are enough to make one wonder if FDE is dead.

The brief -- and slightly qualified -- answer is no. There are a handful of clever attacks, as well as software to make them easier to pull off. Luckily there are easy ways to prevent most of them. We will start, however, with an attack that doesn't have an easy defense.