Thought this was part of the newer AES-XTS option and it needed me to reboot before asking me for password.

It did NOT ask me for a password! I felt this odd, as I didn't have TPM on this machine (yet).

I believe I selected 'Used' not 'entire disk' but, I can't remember.

Rebooted back into Wind#1, the old Windows, and enabled BitLocker on this one drive.

Note that Windows Boot Loader is now defaulting to Wind#2, as it was the version I just installed.

Enabled Developer Insider on this 2nd installation.Installed Windows 10 Pro 1607 from ISO from MSDN, all security updates, rollups, etc.Shrank partition from 1 TB down to 512 GB, had 1 empty 512 GB at the end of disk.Had Windows installed, with 'Developer Insider' enabled and all absolutely latest version of Previews (Bash, etc).If that does not apply to you, I am afraid your partition is broken.Ĭhiming in, as that is the problem I am facing - AES-XTS screwed everything up: In the meantime: the only time I saw a key not working was when I tried to open a bitlocked partition that was encrypted using AES-XTS (the default encryption method of windows 10 v1511 and higher) on a downlevel OS like win7/8.1 or even on win10 10240. Geortge, please open a separate question.

Windows key s not working