File Corruption Occurs on an NTFS Volume with More Than 4 Million Files

ID: Q229607

The information in this article applies to:
  • Microsoft Windows NT Server version 4.0
  • Microsoft Windows NT Workstation version 4.0
  • Microsoft Windows NT Server, Enterprise Edition version 4.0

SYMPTOMS

When you create and delete files on an NTFS volume that holds more than 4 million files, you see file corruption that may show up in one of the following ways:

  • Deleted files continue to be displayed on the drive.


  • Files that you have not deleted are no longer accessible.


  • A pop-up message is displayed reporting that corruption has been detected on the drive and requesting that you run CHKDSK.



CAUSE

This problem occurs when the Master File Table (MFT) has grown larger than 4 GB, which may happen when you have more than 4 million files on your computer. When you delete a file whose MFT entry is beyond the 4 GB point under these conditions, an error in calculations causes the wrong entry to be marked as available. If this entry contains information for another file, and new files are added to the volume shortly after the deletion occurs, the entry could be re-used causing the file it actually referenced to be lost.


RESOLUTION

To resolve this problem, obtain the latest service pack for Windows NT 4.0 or the individual software update. For information on obtaining the latest service pack, please go to:

For information on obtaining the individual software update, contact Microsoft Product Support Services. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web:
http://www.microsoft.com/support/supportnet/overview/overview.asp

This hotfix has been posted to the following Internet location as Ntfsfixi.exe (x86) and Ntfsfixa.exe (Alpha):
ftp://ftp.microsoft.com/bussys/winnt/winnt-public/fixes/usa/NT40/hotfixes-postSP5/Ntfs-fix/


STATUS

Microsoft has confirmed this to be a problem in the Microsoft products listed at the beginning of this article. This problem was first corrected in Windows NT 4.0 Service Pack 6.


MORE INFORMATION

Information on all files in an NTFS volume is stored in the MFT. The MFT contains one or more an entries for all files on the system. In addition, the MFT maintains empty or unused entries which can be used for newly created files. When a file is deleted, it's entry is marked as being unused so that when a new file is created, the file system can re-use the entry.

Additional query words: sfm services for macintosh

Keywords : kbbug4.00 kbfix4.00
Version : winnt:4.0
Platform : winnt
Issue type : kbbug


Last Reviewed: October 28, 1999
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