Slow network performance when you open a file that is located in a shared folder on a remote network computer

This article helps fix a slow network performance issue that can occur when you open a file that is located in a shared folder on a remote network computer.

Original product version:   Windows 7 Service Pack 1
Original KB number:   829700

Symptoms

When you use Windows Explorer to connect to a shared folder on a remote computer on your network, and you double-click a file in that shared folder to open it, it may take a longer time than expected to open the file. For example, you may experience this issue when you open a Microsoft Office document over a slow connection, such as a 64-kilobits-per-second (kbps) Integrated Services Digital Network (ISDN) connection on a wide area network (WAN).

Cause

This issue occurs because Windows Explorer tries to obtain detailed information about the remote share and about the file that you are opening. This operation may take a long time over a slow connection.

Resolution

Important

This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base: 322756 How to back up and restore the registry in Windows

  1. Add the SuppressionPolicy DWORD value to the following registry key: HKEY_CLASSES_ROOT\*\Shellex\PropertySheetHandlers\CryptoSignMenu
    To do so:

    1. Click Start, and then click Run.

    2. In the Open box, type regedit, and then click OK.

    3. Locate and then click the following registry key: HKEY_CLASSES_ROOT\*\Shellex\PropertySheetHandlers\CryptoSignMenu

    4. On the Edit menu, point to New, and then click DWORD Value.

    5. Type SuppressionPolicy, and then press ENTER.

    6. On the Edit menu, click Modify.

    7. Click Hexadecimal, type 100000 in the Value data box, and then click OK.

  2. Add the SuppressionPolicy DWORD value to the following registry key: HKEY_CLASSES_ROOT\*\Shellex\PropertySheetHandlers\{3EA48300-8CF6-101B-84FB-666CCB9BCD32}
    To do so:

    1. In Registry Editor, locate and then click the following registry key: HKEY_CLASSES_ROOT\*\Shellex\PropertySheetHandlers\{3EA48300-8CF6-101B-84FB-666CCB9BCD32}

    2. On the Edit menu, point to New, and then click DWORD Value.

    3. Type SuppressionPolicy, and then press ENTER.

    4. On the Edit menu, click Modify.

    5. Click Hexadecimal, type 100000 in the Value data box, and then click OK.

  3. Add the SuppressionPolicy DWORD value to the following registry key: HKEY_CLASSES_ROOT\*\Shellex\PropertySheetHandlers\{883373C3-BF89-11D1-BE35-080036B11A03}
    To do so:

    1. In Registry Editor, locate and then click the following registry key: HKEY_CLASSES_ROOT\*\Shellex\PropertySheetHandlers\{883373C3-BF89-11D1-BE35-080036B11A03}
    2. On the Edit menu, point to New, and then click DWORD Value.
    3. Type SuppressionPolicy, and then press ENTER.
    4. On the Edit menu, click Modify.
    5. Click Hexadecimal, type 100000 in the Value data box, and then click OK.
  4. Add the Flags DWORD value to the following registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\SCAPI
    To do so:

    1. In Registry Editor, locate and then click the following registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\SCAPI

    2. On the Edit menu, point to New, and then click DWORD Value.

    3. Type Flags, and then press ENTER.

    4. On the Edit menu, click Modify.

    5. Click Hexadecimal, type 00100c02 in the Value data box, and then click OK.

    6. Quit Registry Editor.

Adding a Group Policy

Besides the direct registry modifications that are described in the "Changing the registry" section, you can also resolve this issue by using a Group Policy. Administrators can control which shell extensions can run by using the Approved key and the EnforceShellExtensionSecurity policy. The SuppressionPolicy value is tied to the EnforceShellExtensionSecurity policy. You can add this policy to enable the modified shell behavior.

To do this, follow these steps:

  1. Click Start, click Run, type Gpedit.msc, and then click OK.
  2. Under User Configuration in the left pane, expand Administrative Templates, expand Windows Components, and then click Windows Explorer.
  3. In the right pane, double-click Allow only per user or approved shell extensions, click Enabled, and then click OK.