FTP commands do not work if the client computer connects to a downstream ISA Server computer where firewall chaining is configured

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SYMPTOMS

You can log the client computer on to external File Transfer Protocol (FTP) sites. You can do this if the client computer is behind the downstream Microsoft Internet Security and Acceleration (ISA) Server computer that is in a firewall chain. However, if you send commands such as ls to the FTP server, you receive the following reply message, and then you receive no other replies from the server:

150 Opening ASCII mode data connection for file list

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CAUSE

The problem occurs if the following conditions are true:

The firewall chaining is configured in the downstream ISA Server computer.
The downstream ISA Server computer points to an upstream ISA Server computer.
The client computer is configured with the firewall client and points to the downstream ISA Server computer.

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RESOLUTION

Service pack information

To resolve this problem, obtain the latest service pack for Internet Security and Acceleration Server 2004. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

891024 (http://support.microsoft.com/kb/891024/ ) How to obtain the latest ISA Server 2004 service pack

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Hotfix information

A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.

If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.

Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site:

http://support.microsoft.com/contactus/?ws=support (http://support.microsoft.com/contactus/?ws=support)

Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.

Prerequisites

For ISA Server 2004 Standard Edition, you must have Service Pack 1 (SP1) installed. For more information about how to obtain the latest ISA Server 2004 service pack, click the following article number to view the article in the Microsoft Knowledge Base:

891024 (http://support.microsoft.com/kb/891024/ ) How to obtain the latest ISA Server 2004 service pack

Restart requirement

You do not have to restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

File Information

The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.

ISA Server 2004 Standard Edition

     Date         Time   Version            Size    File name
   --------------------------------------------------------------
   16-May-2005  03:57  4.0.2163.269      934,672  Wspsrv.exe

ISA Server 2004 Enterprise Edition

        Date         Time   Version            Size    File name
   --------------------------------------------------------------
   01-Jun-2005  08:00  4.0.3440.269    1,058,072  Wspsrv.exe

Note This hotfix is only required on the downstream ISA Server computer.

After you apply the hotfix

After you apply the hotfix on the downstream ISA Server computer, use the following script to manually turn on the EnableDownstreamSecondary option:

Sub AddEnableSecondary()

    ' Create the root object.
    Dim root  ' The FPCLib.FPC root object
    Set root = CreateObject("FPC.Root")

    'Declare the other objects needed.
    Dim array       ' An FPCArray object
    Dim VendorSets  ' An FPCVendorParametersSets collection
    Dim VendorSet   ' An FPCVendorParametersSet object

    ' Get references to the array object
    ' and the network rules collection.
    Set array = root.GetContainingArray
    Set VendorSets = array.VendorParametersSets

    On Error Resume Next
    Set VendorSet = VendorSets.Item( "{143F5698-103B-12D4-FF34-1F34767DEabc}" )

    If Err.Number <> 0 Then
        Err.Clear

        ' Add the item
        Set VendorSet = VendorSets.Add( "{143F5698-103B-12D4-FF34-1F34767DEabc}" )
        CheckError
        WScript.Echo "New VendorSet added... " & VendorSet.Name

    Else
        WScript.Echo "Existing VendorSet found... value- " &  VendorSet.Value("EnableDownstreamSecondary")
    End If

    if VendorSet.Value("EnableDownstreamSecondary") <> true Then

        Err.Clear
        VendorSet.Value("EnableDownstreamSecondary") = true

        If Err.Number <> 0 Then
            CheckError
        Else
            VendorSets.Save false, true
            CheckError

            If Err.Number = 0 Then
                WScript.Echo "Done with EnableDownstreamSecondary, saved!"
            End If
        End If
    Else
        WScript.Echo "Done with EnableDownstreamSecondary, no change!"
    End If

End Sub

Sub CheckError()

    If Err.Number <> 0 Then
        WScript.Echo "An error occurred: 0x" & Hex(Err.Number) & " " & Err.Description
        Err.Clear
    End If

End Sub

AddEnableSecondary

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STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section. This problem was first corrected in Internet Security and Acceleration Server 2004 Service Pack 2.

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MORE INFORMATION

For more information about how to install ISA Server 2004 hotfixes and updates, click the following article number to view the article in the Microsoft Knowledge Base:

885957 (http://support.microsoft.com/kb/885957/ ) How to install ISA Server hotfixes and updates

For more information about the standard terminology that is used to describe Microsoft software updates, click the following article number to view the article in the Microsoft Knowledge Base:

824684 (http://support.microsoft.com/kb/824684/ ) Description of the standard terminology that is used to describe Microsoft software updates

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