XFOR: Dequeing SMTP Mail Outside of Dialup Connections (175494)



The information in this article applies to:

  • Microsoft Exchange Server 5.0
  • Microsoft Exchange Server 5.5

This article was previously published under Q175494
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

Microsoft Exchange Server has the ability to send a command or ETRN (with version 5.0 Service Pack 1) to another host to prompt that host to send any messages waiting for the specified domain (also known as "dequeuing").

However, by default, this functionality is limited to only dial-up connections.

If this functionality is required outside of the dial-up connections of the Internet Mail Service (like in the case of Dial-up or Dial-on-demand routers), you must use some method to send this command manually, either through a batch file or the use of a third-party dequeing application.

WORKAROUND

Create a batch file to run on Windows NT AT Command Scheduler (available in the Windows NT Resource Kit) or other third-party scheduling application. The following are example batch files:

Example 1: (assumes Internet Mail Service is always running)
PING <other_hosts_ip_address> ---> makes the dialup router initiate its connection
PING <other_hosts_ip_address> ---> verify connection
FINGER My.DomainA.Com@ISP.Host.DomainB.Com ---> to dequeue
				
Example 2: (assumes Internet Mail Service is always running)
PING <other_hosts_ip_address> ---> makes the dialup router initiate its connection
PING <other_hosts_ip_address> ---> verify connection
<Retrieval Program> ---> third-party program that dequeues mail
				
Example 3: (assumes Internet Mail Service is NOT running)
PING <other_hosts_ip_address> ---> makes the dialup router initiate its connection
PING <other_hosts_ip_address> ---> verify connection
NET START MSExchangeIMC ---> starts the Internet Mail Service
<Retrieval Method: command or executable>
NET STOP MSExchangeIMC ---> stops the Internet Mail Service
				
Also, if the ability to use ETRN is needed outside of dial-up connections, there is another workaround available. The ETRN command can be configured to be sent to all hosts the Internet Mail Service connects to. To do so, use the following steps.

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.
  1. Start Registry Editor (Regedt32.exe).
  2. Locate the following key in the registry:
    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeIMC
    \Parameters
    						
    NOTE: The above registry key is one path; it has been wrapped for readability.
  3. On the Edit menu, click Add Value, and then add the following registry value:

    Value Name: AlwaysUseETRN
    Data Type: REG_DWORD
    Value: 0x1

  4. Quit Registry Editor.
Setting this entry tells the Internet Mail Service to send the ETRN command to any ESMTP hosts it connects to (that advertise they support ETRN). This will use any domains listed on the routing table configured with the Internet Mail Service.

NOTE: It is recommended that this entry be used only when forwarding messages to a single host. This is due to the added time it takes to send and wait for a response to the ETRN command.
' ------------------------------------------------------------------------
' Q241157  Script to enable ETRN for IMS on LAN or Demand Dial Networks
' ------------------------------------------------------------------------
'               Copyright (C) 1996-2000 Microsoft Corporation
'
' You have a royalty-free right to use, modify, reproduce and distribute
' the Sample Application Files (and/or any modified version) in any way
' you find useful, provided that you agree that Microsoft has no warranty,
' obligations or liability for any Sample Application Files.
' ------------------------------------------------------------------------
				
Windows Script Host must be installed http://msdn.microsoft.com/scripting
Choice = InputBox("Enter 1 to enable ETRN or 2 to disable ETRN")

Select Case Choice

Case "1"

L_Welcome_MsgBox_Message_Text   = "This script adds the AlwaysUseETRN value to the Internet Mail Service that enables LAN based ETRN."
L_Welcome_MsgBox_Title_Text     = "Enabling ETRN"
Call Welcome()
Dim WSHShell
Set WSHShell = WScript.CreateObject("WScript.Shell")
WSHShell.Popup "Set value HKLM\System\CurrentControlSet\Services\MSExchangeIMC\Parameters\AlwaysUseETRN to REG_DWORD 1"
WSHShell.RegWrite "HKLM\System\CurrentControlSet\Services\MSExchangeIMC\Parameters\AlwaysUseETRN" , 1, "REG_DWORD"

Case "2"
L_Welcome_MsgBox_Message_Text   = "Setting the Value AlwaysUseETRN to zero"
L_Welcome_MsgBox_Title_Text     = "disabling ETRN"
Call Welcome()
Set WSHShell = WScript.CreateObject("WScript.Shell")
WSHShell.Popup "Set value HKLM\System\CurrentControlSet\Services\MSExchangeIMC\Parameters\AlwaysUseETRN to REG_DWORD 0"
WSHShell.RegWrite "HKLM\System\CurrentControlSet\Services\MSExchangeIMC\Parameters\AlwaysUseETRN" , 0, "REG_DWORD"

End Select

Sub Welcome()
    Dim intDoIt

    intDoIt =  MsgBox(L_Welcome_MsgBox_Message_Text, vbOKCancel + vbInformation, L_Welcome_MsgBox_Title_Text )
    If intDoIt = vbCancel Then
        WScript.Quit
    End If
End Sub
				

Modification Type:MinorLast Reviewed:4/21/2005
Keywords:kbprb KB175494