You cannot access a newly copied file in a shared folder on a computer that is running Windows Server 2008 or Windows Vista

Consider the following scenario:

• You have three computers that are running Windows Server 2008 or Windows Vista in a local area network (LAN). One of the computers is a server message block (SMB) file server. The other two computers are clients of the SMB file server.
• You create two shared folders on the computer that is a SMB file server.
• You map both shared folders on one of the computers that is a client of the SMB file server.
• You copy a file from one of the shared folders to a local drive by using the CopyFile() function on the computer that you mapped both shared folders.
• You copy a different file from this shared folder to the other shared folder by using the CopyFile() function on the computer that you mapped both shared folders.
• You try to access this copy of the second file from another computer that is a client of the SMB file server.

In this scenario, you cannot access the file, and you receive the following error message: If you try to access the same file again several seconds later, you can access it.

For example, assume the following:

• The computer that is the SMB file server is called computer 1.
• The computers that are clients of the SMB file server are called computer 2 and computer 3.
• You create two shared folders that are called share 1 and share 2 on computer 1.
• You map share 1 and share 2 on computer 2.
• You copy a file from share 1 to a local drive on computer 2 by using the CopyFile() function.
• You copy a different file from share 1 to share 2 by using the CopyFile() function.
• You use computer 3 to access this copy of the second file.

In this scenario, you cannot access the file, and you receive the error message. However, you can access the file after 10 seconds.

This issue occurs because the SMB 2.0 protocol keeps an oplock unnecessarily after a file copy operation is completed. Any access to the file from a system other than the copy originator is denied for approximately 10 seconds.

Hotfix information

Note To resolve this issue, install the hotfix on all three computers in the LAN environment.

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 the problem described in this article. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.

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, contact 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.

Prerequisites

To apply this hotfix, your computer must be running one of the following operating systems:

• Windows Vista Service Pack 2 (SP2)
• 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: 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:

Restart requirement

You must restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace a previously released hotfix.

File information

The English (United States) 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 2 . 22xxx

  Windows Vista and Windows Server 2008

  SP2

  LDR

• 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

Workaround for Windows Vista and for Windows Server 2008

To work around this issue, disable SMBv2. To do this, follow these steps:

1. Click Start , type regedit in the Start Search box, and then press ENTER.
2. Locate and then click the following registry subkey:
   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\LanmanServer\Parameters
3. On the Edit menu, point to New, and then click DWORD Value.
4. Type SMB2, and then press ENTER.
5. On the Edit menu, click Modify.
6. Type 0 (zero), and then click OK
7. Exit Registry Editor.
8. Restart the computer.

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: For more information the CopyFile function, visit the following Microsoft Developer Network (MSDN) Web site:

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

Additional files for all supported x64-based versions of Windows Vista and of Windows Server 2008

Additional files for all supported IA-64-based versions of Windows Server 2008