I’ve been using NTFS for almost a year now and I’ve like its stability and low maintenance. NTFS doesn’t fragment as much and allows for greater disk security. However, ever since I installed Windows XP, I’ve gotten a cryptic error when running chkdsk.exe from the command line. I talked to Microsoft and one of their tech support agents replied back today. Read on to see how the conversation went.
My initial post
Problem Description: I’ve been running Windows XP Home for almost a year now. I have been using it with my other computer, a Dell Dimension 8100. The problem started with that machine but I have seen it now manifest on this one as well. Originally that system ran Windows ME (Dell installed) and then I upgraded it to XP Home using the XP upgrade CD. I converted the file systems on that machine to NTFS via the command prompt. I have three hard drives on that machine, two of which are EIDE and the third is firewire.
I noticed that somehow a glitch happened in my NTFS file system on that machine. I started getting messages identical to the attached file, chkdsk.txt. I would run chkdsk while logged on and it would say that there is an error with my volume bitmap. However, this error only appears when checking C:, not the other two hard drives.
When I went to upgrade this computer, I backed up all of the files across my HPNA (homeclick homeconnect) home network to my firewire drive on the Dimension 8100. I then clean installed Windows XP Home on this machine using a store bought boxed upgrade edition of XP. I did a long NTFS format of the primary drive. I installed all of my essential programs and ran a disk check via the command prompt. The error had not manifested.
However, the minute I copied files from my firewire drive on the other computer, chkdsk reported volume bitmap errors on my freshly installed copy of XP on this machine. This leads me to believe that there is some sort of “glitch” or error in my documents that messes up the NTFS file system.
The documents are primarily graphics (GIF, JPG), Word documents, or MP3s. I had recently run a virus scan and nothing came up.
CHKDSK recommends to run a check with the /F switch, and I did that. Windows just doesn’t repair the error. I don’t know if there is anything wrong with CHKDSK, but this error has now appeared on three of my computers, including one that was running Windows 2000.
I was wondering if there is any way to resolve this error. I am willing to format to FAT32 to get rid of the problem, but three of the hard drives I own are over 32GB and Windows XP will not format them to FAT32.
Any ideas? Thanks.
Microsoft’s reassuring answer
As I understand, the issue is: You received the following error report when performing chkdsk.exe tool on your Windows XP:
Security descriptor verification completed.
Correcting errors in the Volume Bitmap.
Windows found problems with the file system.
Run CHKDSK with the /F (fix) option to correct these.
If I have misunderstood your concerns please let me know.
According to my research, I have included the following information for your reference:
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 chkntfs <drive letter>:. If this command reports that dirty bit is set, there may be real damage that needs to be fixed.