Have you tried running a disk sector scanner such as HDDregenorator, HDAT2 4.53 or
and/or HDD Scan 3.3?
I would do the following steps to ensure there is no corruptions with data, especially with the vital SEE files:
1 - Run Hdat2 (free) or HHDregenorator (Free version will only fix one sector). This will scan and fix any damaged sectors basically making the data readable again. Don't use offline disk utilities that try to move files off a bad sector onto a healty sector. BIG NO NO with encryption.
2 - Once the sectors are fixed / verified, run the recover utility and make sure the SEE file integrity is in check. Recover /a I think, whatever is the first test that runs.
Once all this is completed, boot into windows and see if the decryption process is fixed. If all else fails run the recover /D option if you have a management server in place.
Hope this helps and good luck! co