A large file download fails when an ISA Server 2006 SOCKS client computer uses passive mode FTP

• The FTP client computer is configured to use the SOCKS protocol.
• The FTP client computer uses ISA Server 2006 for outgoing passive FTP access.
• The idle connection time-out value in ISA Server 2006 is set to the default value of 120 seconds.

• Data is not sent over the control channel during the download operation.
• A passive mode FTP file download takes longer than 120 seconds.

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How to obtain the hotfix

File size / download speed * 1.2 = time-out (seconds)

(200 * 8) / 1 * 1.2 = 1920 seconds

1. Start Notepad.
2. Copy the following script into the Notepad file. Then, save the file to the ISA Server 2006 computer, and use a file name that has a .vbs extension, such as SetSocksIdleTimeout.vbs.

   <Script>
   
   ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
   '
   ' Copyright (c) Microsoft Corporation. All rights reserved.
   ' THIS CODE IS MADE AVAILABLE AS IS, WITHOUT WARRANTY OF ANY KIND. THE ENTIRE
   ' RISK OF THE USE OR THE RESULTS FROM THE USE OF THIS CODE REMAINS WITH THE
   ' USER. USE AND REDISTRIBUTION OF THIS CODE, WITH OR WITHOUT MODIFICATION, IS
   ' HEREBY PERMITTED.
   ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
   
   ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
   ' This script sets the idle connection time-out value for the SOCKS filter.
   ' The value is in seconds.
   ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
   
   Sub SetSocksIdleTimeout()
   
       ' 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 Extensions  ' An FPCExtensions object
       Dim ApplicationFilters ' An FPCApplicationFilters object
       Dim ApplicationFilter  ' An FPCApplicationFilter object
       Dim VendorSets  ' An FPCVendorParametersSets collection
       Dim VendorSet   ' An FPCVendorParametersSet object
   
       ' Get references to the array object
       Set array = root.GetContainingArray
   
       On Error Resume Next
   
       Set Extensions = array.Extensions
       CheckError
   
       Set ApplicationFilters = Extensions.ApplicationFilters
       CheckError
   
       Set ApplicationFilter = ApplicationFilters.Item("{25765C04-C80B-494C-914E-286297DB8C8E}")
   
       Set VendorSets = ApplicationFilter.VendorParametersSets
       Set VendorSet = VendorSets.Item( "{25765C04-C80B-494C-914E-286297DB8C8E}" )
   
       VendorSet.Value("SessionIdleTimeoutSeconds") = 120 ' value in seconds to be set to desired value
   
       ApplicationFilter.Save false, true
   
       WScript.Echo "Done..."
   
   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
   
   SetSocksIdleTimeout
   
   </Script>

3. This script uses the default time-out value of 120 seconds. Change the time-out value to the setting that you want, and then save the script.
4. Double-click the .vbs file to run the script.

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