from microsoft. you can try chkdsk/F
This problem occurs because when Chkdsk is run against an NTFS volume,
Chkdsk.exe may report that security descriptors are in the database that are
no longer referenced by any file or folder, and that it is removing them.
However, Chkdsk.exe just reclaims the unused security descriptors as a
housekeeping activity, and is not actually fixing any kind of problem.
Microsoft has confirmed that this is a problem in Windows. Fortunately, this
error message is an informational message, and can be safely ignored.
All NTFS volumes contain a security descriptor database. This database is
populated with security identifiers that represent unique permission
settings applied to files and folders. When files or folders have unique
NTFS permissions applied, NTFS stores a unique security descriptor once on
the volume, and also stores a pointer to the security descriptor on any file
or folder that references it.
If files or folders no longer use that unique security descriptor, NTFS does
not remove the unique security descriptor from the database, but instead,
keeps it cached. Like any caching strategy, you want to keep the cached
information as long as possible because it may be used again.
To determine if more serious problems exist before scheduling or running
Chkdsk.exe with the /f switch, run the "chkntfs :" (without
the quotation marks) command, where is the drive letter of the drive you
want to run the "chkdsk /f" (without the quotation marks) command against.
If this command reports that the "dirty bit" is set, there may be real
damage that needs to be fixed.