After using the file shredder on some files, folders, drives or free space, the items that you shredded will NOT be recoverable. It is extremely unlikely that someone will ever be able to recover the data you shredded.
This is why we take the extra precaution of asking you if you really, really want to delete the information.
This question is needed in order to avoid possible accidents - people shredding files, and then being very sorry because they can't recover anything (this is the very purpose of the File Shredder tool, but some people may be using it by mistake).
More information about the File Shredder tool