The Universal Naming Convention Shortcuts Do Not Work Over Remote Access Service to a Server with More Than 700 Shares (232937)

IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base:

256986 Description of the Microsoft Windows Registry

SYMPTOMS

When a user attempts to connect to a share that is located on another computer by double-clicking an icon that points to that share (a shortcut), if that icon contains a universal naming convention (UNC) path to a share on a remote computer, and your computer gains access to that computer by using a Remote Access Service (RAS) connection, the connection may be unsuccessful and the icon may change to a Microsoft default icon.

CAUSE

This problem can occur because the WNetGetResourceInformation() function on the client retrieves all share names from the remote computer when the function accesses one of the remote shares by means of the shortcut on the client. The WNetGetResourceInformation() function has a built-in timer (NetLinkTimeout) with a default time-out value of 7.5 seconds. To retrieve a relatively large number of shares over a slow RAS link takes longer than 7.5 seconds, in most situations.

A "relatively large number of shares" has been empirically determined to be about 700 shares, but this number may be larger or smaller depending upon the data rate that is achieved over the RAS connection between the client and the server.

RESOLUTION

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

To resolve this problem, add the following registry key:

Start Registry Editor (Regedt32.exe).
Locate and click the following key in the registry:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer
On the Edit menu, click Add Value, and then add the following registry value:
Value name: NetLinkTimeout
Data type: REG_DWORD
Unit: milliseconds
Default: N/A (hard coded to 7500)
Quit Registry Editor.

You need to create this value because it does not exist by default. Initially, set the value to 9000 (9 seconds). If time-out behaviors persist, increase this value in 500 millisecond increments until the time-out behavior stops.

The time-out value in the preceding registry key must only be modified on the computer that connects to the shares.

REFERENCES

For additional information, click the article number below to view the article in the Microsoft Knowledge Base:

255772 Long Delay When Displaying Icons in Start Menu Subfolder