From LedHed's Wiki
Overview
If you use BitLocker and find yourself in a situation where upon reboot your computer keeps prompting you for a BitLocker Recovery Password you may have exceeded the max number of password attempts.
Solution
While in Windows Recovery (WinRE) run the following commands:
manage-bde -status c:
If the status comes back as 'Locked' then:
manage-bde -unlock c: -rp <your 48-digit recovery password>
manage-bde -protectors -disable c:
Once you've booted back into Windows, you can resume BitLocker protection by going to the control panel and clicking 'Manage BitLocker'