Ntfs.sys driver takes a long time to mount a large volume in Windows Vista or in Windows Server 2008
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Applies to: Windows Vista StarterWindows Vista Home PremiumWindows Vista Home BasicWindows Vista BusinessWindows Vista EnterpriseWindows Vista UltimateWindows Server 2008 StandardWindows Server 2008 FoundationWindows Server 2008 Standard without Hyper-VWindows Server 2008 Enterprise without Hyper-VWindows Server 2008 Datacenter without Hyper-VWindows Server 2008 for Itanium-Based SystemsWindows Server 2008 EnterpriseWindows Server 2008 DatacenterMore
On a computer that is running Windows Vista or Windows Server 2008, the Ntfs.sys driver takes a long time (several seconds or minutes) to mount a large volume.
This issue causes a delay in volume arrival and in volume mounting. Therefore, applications and services may be unable to access the volume.
During the volume mounting process, the Ntfs.sys driver reads the $Bitmap file to retrieve the number of free clusters in the current volume. If the file size of the $Bitmap file is large and the current cluster size is set to a small value such as the default cluster size, the Ntfs.sys driver requires a long time to read the file.
Note The file size of the $Bitmap file is large if the volume size is large.
After you apply the following hotfix, the Ntfs.sys driver pre-fetches the subsequent pages of the $bitmap file to improve performance.
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem.
If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, submit a request to Microsoft Customer Service and Support to obtain the hotfix.
Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site:
Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.
To apply this hotfix, you must be running one of the following operating systems:
Windows Vista Service Pack 1 (SP1)
Windows Vista Service Pack 2 (SP2)
Windows Server 2008
Windows Server 2008 Service Pack 2 (SP2)
For more information about how to obtain a Windows Vista service pack, click the following article number to view the article in the Microsoft Knowledge Base:
935791 How to obtain the latest Windows Vista service pack
For more information about how to obtain a Windows Server 2008 service pack, click the following article number to view the article in the Microsoft Knowledge Base:
968849 How to obtain the latest service pack for Windows Server 2008
To use the hotfix in this package, you do not have to make any changes to the registry.
You must restart the computer after you apply this hotfix.
Hotfix replacement information
This hotfix does not replace a previously released hotfix.
The global version of this hotfix installs files that have the attributes that are listed in the following tables. The dates and the times for these files are listed in Coordinated Universal Time (UTC). The dates and the times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and the times may change when you perform certain operations on the files.
Windows Vista and Windows Server 2008 file information notes
Important Windows Vista hotfixes and Windows Server 2008 hotfixes are included in the same packages. However, only "Windows Vista" is listed on the Hotfix Request page. To request the hotfix package that applies to one or both operating systems, select the hotfix that is listed under "Windows Vista" on the page. Always refer to the "Applies To" section in articles to determine the actual operating system that each hotfix applies to.
The files that apply to a specific product, SR_Level (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table.
6.0.600 1. 22xxx
Windows Vista and Windows Server 2008
6.0.600 2. 22xxx
Windows Vista and Windows Server 2008
Service Pack 1 is integrated into the release version of Windows Server 2008. Therefore, RTM milestone files apply only to Windows Vista. RTM milestone files have a 6.0.0000.xxxxx version number.
The MANIFEST files (.manifest) and the MUM files (.mum) that are installed for each environment are listed separately in the "Additional file information for Windows Server 2008 and for Windows Vista" section. MUM files and MANIFEST files, and the associated security catalog (.cat) files, are extremely important to maintain the state of the updated components. The security catalog files, for which the attributes are not listed, are signed with a Microsoft digital signature.
For all supported x86-based versions of Windows Server 2008 and of Windows Vista
For all supported x64-based versions of Windows Server 2008 and of Windows Vista
For all supported IA-64-based versions of Windows Server 2008
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:
824684 Description of the standard terminology that is used to describe Microsoft software updates
For more information about a similar issue that occurs in Windows Server 2003 SP2, click the following article number to view the article in the Microsoft Knowledge Base:
969352 A long delay occurs when the Ntfs.sys driver tries to mount a large volume on a computer that is running Windows Server 2003 SP2
Additional file information
Additional file information for Windows Vista and for Windows Server 2008
Additional files for all supported x86-based versions of Windows Vista and of Windows Server 2008