Windows users seem to be experiencing an issue with enabling BitLocker hardware encryption after updating to their system to November update, which Microsoft is calling its major update to Windows 10 that brings version 1511, build 10586. This happens with the clean installation of the November update.
Windows BitLocker drive encryption is a security feature that Microsoft claims provides better data protection for your PC by encrypting the data stored on your Windows operating system volume. BitLocker uses Trusted Platform Module (TPM) to protect Windows OS and data as well as ensures the computer is not tampered with even when it is lost. The TPM is a microchip built into the computer and used to store information including encryption keys.
You can use BitLocker without a TPM, for which you need to change the default behaviour of the BitLocker setup wizard by using Group Policy, or configure BitLocker. When you are using BitLocker without TPM, the encryption keys are stored on a USB flash drive.
BitLocker encryption issue with November Update
According to a user, nesoi, who has reported this on the Microsoft TechNet forum, the BitLocker encryption worked fine before the update. It even works with Windows 10 build 10240, which is the RTM build, released prior to the November update. Users on Reddit also reported the same issue.
Nesoi further claims performing a clean installation of build 1058 while trying to start encryption, but the wizard displays an error message saying "parameter is incorrect". If you have enabled encryption on Windows 10 build 10240 and then upgrade to build 10586, the encryption works fine.
While there is no official word so far, an unofficial workaround is available. If you want BitLocker hardware encryption on build 10586, install the previous build 10240, encrypt it and then install the November update.
Microsoft recently said the November update was meant to be originally available via the MCT (Media Creation Tool), but future updates should be available through Windows Update only, as the November update. "People can still download Windows 10 [Build 10240] using the MCT tool if they wish," says the company.