BUG: RasDial() Function Gets Slower with Large Number of Redials (265152)


The information in this article applies to:

  • Microsoft Windows 2000 Server SP1
  • Microsoft Windows 2000 Advanced Server SP1
  • Microsoft Windows 2000 Professional SP1
  • Microsoft Windows NT Server 4.0
  • Microsoft Windows NT Workstation 4.0
This article was previously published under Q265152
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

If the RasDial function is used to make a large number of repetitive dials, performance begins to slow down after thousands of cycles. This problem occurs only when you are dialing numbers that do not use a phone-book entry.

CAUSE

Windows NT 4.0 and Windows 2000 use the registry to cache information for each successful RasDial attempt. After several thousand cycles, the registry grows very large and performance degrades as the operating system searches to the end of the registry hive.

RESOLUTION

You can work around this problem by disabling password caching.

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 disable the password-caching feature for Remote Access Service (RAS), perform the following steps:
  1. Start Registry Editor (Regedt32.exe), and then select the following subkey:

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\RasMan\Parameters

  2. On the Edit menu, click Add Value, and then type the following information:

    Value Name: DisableSavePassword
    Value Type: REG_DWORD
    Value Data: 1

STATUS

Microsoft has confirmed that this is a bug in the Microsoft products that are listed at the beginning of this article.

MORE INFORMATION

Steps to Reproduce Behavior

To reproduce this behavior, obtain the RasDial sample from the Microsoft Platform SDK and call it repetitively from a batch file, using command-line arguments for the user, password, domain, and telephone number. After several hours, notice that each connection takes longer and longer.
Modification Type:MajorLast Reviewed:5/14/2003
Keywords:kbbug kbpending KB265152
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