If you encounter an issue where a user changed their password recently and they cannot login to their computer encryption system then do the following actions when logged in as an administrator:
sudo fdesetup add -usertoadd <UFNET USERNAME>
After hitting enter, this is what happens in terminal:
Enter the user name: "TYPE" administrator
Enter the password for user 'administrator':
Enter the password for the added user '<UFNET USERNAME>':
Without doing the above this may also work:
I’ve worked out the following procedure that the end users and IT support/help desk will have to follow unless Apple change this ridiculous behaviour:
1. Unlock the drive using your old password (despite having changed your password externally).
2. After unlocking, if the computer is on the corporate network, the Login Window will bounce and prompt for your password – type in your new password.
3. You’ll be prompted about the OS not being able to unlock your Keychain – click “Update Keychain Password”.
4. Once the login has completed, restart the computer.
5. Unlock the drive using your OLD password.
6. After unlocking, the Login Window will bounce still and prompt for your password – type in your new password again.
7. Once the login has completed, restart the computer again.
8. You will now finally be able to unlock using your new password at the next restart.