Knowledge Base

RasDial( ) Leaks Resources on WinNT 4.0

Article ID: 168348

Article Last Modified on 11/1/2006

APPLIES TO

This article was previously published under Q168348

SYMPTOMS

When an application repeatedly calls the RasDial( ) and RasHangup( ) APIs, memory and handle leaks may be observed. One consequence of these leaks is that Remote Access Service (RAS) can no longer dial out after a certain number of iterations.

You may experience this problem as your Windows NT RAS client makes repeated connections without rebooting the computer.

CAUSE

The Win32 API RAS APIs that are used for connection management do not de-allocate all of the memory they use. Any process that repeatedly establishes and tears down connections will cause an increased use of memory and resources. An increase in the number of system handles used by the process may also be observed.

RESOLUTION

Update to the latest Microsoft Windows NT 4.0 U.S. Service Pack.

STATUS

Microsoft has confirmed this to be a problem in Windows NT version 4.0. This problem was corrected in the latest Microsoft Windows NT 4.0 U.S. Service Pack. For information on obtaining the service pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

S E R V P A C K

MORE INFORMATION

To identify this as the cause of the problem, perform the following steps:
  1. Open Task Manager (right click the Taskbar and select Task Manager).
  2. Click Processes.
  3. Click View, select Select Columns.
  4. Check Handle Count.
  5. Click OK.
  6. Watch the Handle Count for applications that use RAS to establish connections. If one process (usually Rasman.exe) appears to show its Handle Count increasing over time, and not decreasing, you are probably experiencing this problem.
This issue may also be caused (or contributed to) by another similar RAS API issue.

For additional information, please see the following article in the Microsoft Knowledge Base:

165483 RasEnumEntries() API leaks memory

Keywords: kbbug KB168348


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