CHKDSK error message - The type of the filesystem is RAW - http://www.z-a-recovery.com/art-raw-filesystem.htm
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See comments by Quietman at This Link.
The "not accessible, incorrect function" message typically seems to occur with optical drives, not hard drives...I would say that either your file system or the drive itself is failing.
A failing file system can be overcome by reformatting and reinstalling the O/S, while a failing hard drive probably needs to be written off, if running the correct hard drive manufacturer's diagnostic
on it confirms the suspicion of imminent failure.