Answer:
Your computer must be TPM compatible
Explanation:
TPM -> Trusted Platform Module.
For BitLocker’s to have its full-disk encryption on any computer, the computer be TPM compatible.
This TPM creates the original encryption keys of the BitLocker, after which the keys are then saved/stored; that's why the BitLocker needs the TPM to function.
On it's own, it can unlock the computer's drive for the user to login to the system by just typing the login pass phrase.
When you try using BitLocker on a computer without TPM, you'll receive a notification that says your administrator must set a system policy option.
