Recovering Ransomlocked Files Using Built-In Windows Tools

Use a Previous Version

An alternative, if it is a technology in use in your organization, is to restore from a Previous Version.  Previous versions are copies of files and folders that Windows automatically saved as part of system protection. This feature is fantastic at rescuing files that were damaged by malware. If system protection is enabled, Windows automatically creates previous versions of files and folders that have been modified since the last restore point was made.

http://www.symantec.com/connect/articles/recovering-ransomlocked-files-using-built-windows-tools