Knowledge Base

Error message when you try to access streaming media content that is routed through a RealNetworks Helix Proxy server that is located behind ISA Server: "Proxy to origin server connection lost"

Article ID: 907848

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
Microsoft Internet Security and Acceleration Server 2000 Standard Edition

SYMPTOMS

You try to access streaming media content that is routed through a server that is running RealNetworks Helix Proxy. This server is located behind a server that is running Microsoft Internet Security and Acceleration (ISA) Server 2004 or Microsoft ISA Server 2000. In this case, you may receive the following error message:

Proxy to origin server connection lost

CAUSE

This behavior occurs when ISA Server 2000 or ISA Server 2004 drops traffic that is sent by the RealNetworks Helix Proxy server and that contains a "x-real-nullsetup" transport header. This transport header is unknown to ISA Server 2000 and to ISA Server 2004.

RESOLUTION

ISA Server 2000 hotfix information

A supported hotfix is now 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 service pack that contains this hotfix.

To resolve this problem, submit a request to Microsoft Online Customer Services to obtain the hotfix. To submit an online request to obtain the hotfix, visit the following Microsoft Web site:

http://go.microsoft.com/?linkid=6294451

Note If additional issues occur or 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. To create a separate service request, visit the following Microsoft Web site:

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

Prerequisites

You must install Microsoft ISA Server 2000 Service Pack 2 (SP2) before you install the hotfix.

Restart requirement

You do not have to restart the computer after you apply the hotfix. However, you must restart the Microsoft Firewall service after you run the script that is described in the "Hotfix installation information" section.

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.

File name	File version	File size	Date	Time	Platform
Msfpcui.dll	3.0.1200.432	2,760,696	19-Sep-2005	06:25	x86
Strmfltr.dll	3.0.1200.432	69,624	19-Sep-2005	06:25	x86

Hotfix installation information

After you install the hotfix, run the following .vbs script on the ISA Server 2000 server. This script adds "x-real-nullsetup" to the list of recognized Real Time Streaming Protocol (RTSP) transport headers. To do this, follow these steps:

Start Notepad.

Copy the following text, and then paste it into Notepad.

Set root = CreateObject("FPC.Root")
Set MyArray = root.Arrays.GetContainingArray
Set rtspFilter = MyArray.Extensions.ApplicationFilters.Item("{473ED0E1-6371-4ED2-9F95-A676B66659A2}")
If rtspFilter is Nothing Then
    Wscript.Echo "RTSP Filter ({473ED0E1-6371-4ED2-9F95-A676B66659A2}) is not installed in array." 
    WScript.Quit
End If
' Get the vendor parameter set that contains the filter's configuration.
Set vpSet = rtspFilter.VendorParametersSets.Item("{473ED0E1-6371-4ED2-9F95-A676B66659A2}")
' Add the required parameter.
vpSet.Value("RtspTransportList") = "RTP/AVP;UDP,X-REAL-RDT/UDP;UDP,X-REAL-RDT/TCP;TCP,X-PN-TNG/UDP;UDP,X-PN-TNG/TCP;TCP,X-REAL-NULLSETUP;TCP"
vpSet.Save

In Notepad, click Save as on the File menu.
In the File name box, type ISA_script_name.vbs, and then click Save.
Quit Notepad.
Copy the ISA_script_name.vbs file to the ISA Server 2000 server.
On the ISA Server 2000 server, open a command prompt, and then move to the directory where you copied the script file.
Type ISA_script_name.vbs, and then press ENTER.
Close the Command Prompt window.
In the Services snap-in, restart the Microsoft Firewall service.

ISA Server 2004 service pack information

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

891024 How to obtain the latest ISA Server 2004 service pack

After you install ISA Server 2004 Service Pack 2 (SP2), you must run a script on the ISA Server 2004 server. To run the script, follow these steps:

Start Notepad.

Copy the following text, and then paste it into Notepad.

Set root = CreateObject("FPC.Root")
Set MyArray = root.GetContainingArray
Set rtspFilter = MyArray.Extensions.ApplicationFilters.Item("{C758F63F-E391-4AD2-AA31-D050D895BA7B}")

If rtspFilter is Nothing Then
    Wscript.Echo "RTSP Filter ({C758F63F-E391-4AD2-AA31-D050D895BA7B}) is not installed in array." 
    WScript.Quit
End If

' Get the vendor parameter set that contains the filter's configuration.
Set vpSet = rtspFilter.VendorParametersSets.Item("{C758F63F-E391-4AD2-AA31-D050D895BA7B}")

' Add the required parameter.
vpSet.Value("RtspTransportList") = "RTP/AVP;UDP,X-REAL-RDT/UDP;UDP,X-REAL-RDT/TCP;TCP,X-PN-TNG/UDP;UDP,X-PN-TNG/TCP;TCP,X-REAL-NULLSETUP;TCP"
vpSet.Save

In Notepad, click Save as on the File menu.
In the File name box, type ISA_script_name.vbs, and then click Save.
Quit Notepad.
Copy the ISA_script_name.vbs file to the ISA Server 2004 server.
On the ISA Server 2004 server, open a command prompt, and then move to the directory where you copied the script file.
Type ISA_script_name.vbs, and then press ENTER.
Close the Command Prompt window.
Click Start, click Run, type Services.msc, and then press Enter.
In the Services snap-in, restart the Microsoft Firewall service.

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

MORE INFORMATION

When ISA Server processes RTSP traffic, ISA Server validates the traffic against several known properties of an RTSP request. ISA Server recognizes the following transports:

RTP/AVP;UDP
X-REAL-RDT/UDP;UDP
X-REAL-RDT/TCP;TCP
X-PN-TNG/UDP;UDP
X-PN-TNG/TCP;TCP

This problem will occur for any transport headers that are not known to ISA Server. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

824684 Description of the standard terminology that is used to describe Microsoft software updates

The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, regarding the performance or reliability of these products.

Keywords: kbbug kbfix kbqfe kbpubtypekc kbhotfixserver KB907848

Microsoft KB Archive/907848

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