This check determines which file system you are using on your hard drive to make sure that it is the NTFS file system, a secured file system that allows you to control or restrict access to individual files or directories. For example, if you want to allow your co-workers to be able to view your files, but not change them, you can do this by using the Access Control Lists (ACLs) provided by NTFS.
Note: For this check to succeed, you must share the drive.
Understanding NTFS File Compression
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