Bitlocker would not accept my recover key...Screw windows update and bitlocker. 1. There has been no hardware change 2. I have the recovery key why don't you accept it. 3. I hate you.
— Sam Stow (@stowgood) October 17, 2016
I was mad! You probably are too if you're reading this, I imagine you are hoping you won't have to rebuild your machine and test the quality of your backups.You have backups right? There is hope. I did have the correct key, and I was not ready to give up yet. I knew my key was right as it was stored in the AD and was found searching for it in the AD as specified here the ID matched:
https://support.microsoft.com/en-gb/kb/928202
So Bitlocker would not accept my key no matter how many times I double check the numbers. Very annoying. One clue when searching for a solution was someone said it seemed to be in a loop it would accept the key bit not get any further.
I then found this wonderful link with a soloution listed as a work around.
http://www.dell.com/support/article/uk/en/ukbsdt1/SLN285155/en
It showed me how to disable bitlocker using the advanced options to get to a CMD window.
This route accepted my recovery key and I was able to disable bitlocker and get back into my surface pro 4. Phew.
You need these two commands.
manage-bde -unlock c: -rp <your 48-digit recovery password>
manage-bde -protectors -disable c:
Make sure you have manage- at the start of both the formatting on the link above made miss it on the second line until I checked why it wasn't recognising the command.
Good luck getting back into your computers/ drives.