I needed this article a few months ago helping out a buddy. My solution (since he didn’t have much of value on it and backups) was to clean the drive and re-install. I think I would still do that but this would be a way to get the data off first.
http://www.makeuseof.com/tag/cryptolocker-is-the-nastiest-malware-ever-heres-what-you-can-do/