Microsoft KB Archive/940708

= The &quot;401 Authentication Required&quot; response that is sent by a Web site is dropped when you use ISA Server 2004 as a Web proxy =

Article ID: 940708

Article Last Modified on 12/4/2007

-

APPLIES TO


 * Microsoft Internet Security and Acceleration Server 2004 Enterprise Edition
 * Microsoft Internet Security and Acceleration Server 2004 Standard Edition

-



SYMPTOMS
Consider the following scenario:
 * You use Microsoft Internet Security and Acceleration (ISA) Server 2004 as a Web proxy to access a Web site.
 * You perform a POST operation on the Web site.
 * The Web site sends a &quot;401 Authentication Required&quot; response to the client.

However, ISA Server drops the &quot;401 Authentication Required&quot; response instead of forwarding the response to the client. This problem may cause the Web access attempt to fail. For example, when you try to upload a large file to the Web site, the upload operation may time out.



RESOLUTION
To resolve this problem, follow these steps:  Apply the hotfix package that is described in the following Microsoft Knowledge Base article:

940709 Description of the ISA Server 2004 hotfix package: July 25, 2007

 Start Notepad.  Copy the following code, and then paste it into Notepad. Const SE_VPS_GUID = &quot;{143F5698-103B-12D4-FF34-1F34767DEabc}&quot; Const SE_VPS_NAME = &quot;AllowPrematureServerResponse&quot; Const SE_VPS_VALUE = true

Sub SetValue

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

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

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

On Error Resume Next Set VendorSet = VendorSets.Item( SE_VPS_GUID )

If Err.Number <> 0 Then Err.Clear

' Add the item. Set VendorSet = VendorSets.Add( SE_VPS_GUID ) CheckError WScript.Echo &quot;New VendorSet added... &quot; & VendorSet.Name

Else WScript.Echo &quot;Existing VendorSet found... value- &quot; & VendorSet.Value(SE_VPS_NAME) End If

if VendorSet.Value(SE_VPS_NAME) <> SE_VPS_VALUE Then

Err.Clear VendorSet.Value(SE_VPS_NAME) = SE_VPS_VALUE

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

If Err.Number = 0 Then WScript.Echo &quot;Done with &quot; & SE_VPS_NAME & &quot;, saved!&quot; End If       End If    Else WScript.Echo &quot;Done with &quot; & SE_VPS_NAME & &quot;, no change!&quot; End If

End Sub

Sub CheckError

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

End Sub

SetValue  Save the file as a Microsoft Visual Basic script file by using the .vbs file name extension. For example, use the following name to save the file:

AllowPrematureServerResponse.vbs

 Start a command prompt, change to the location at which you saved the AllowPrematureServerResponse.vbs file, and then run the following command:

cscript AllowPrematureServerResponse.vbs





STATUS
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the &quot;Applies to&quot; section.

Additional query words: silently drops target

Keywords: kbqfe kbexpertiseinter KB940708

-

[mailto:TECHNET@MICROSOFT.COM Send feedback to Microsoft]

© Microsoft Corporation. All rights reserved.