The Sender ID filter may reject e-mail that is sent from an IP address that is associated with an SPF record that contains "v=spf1 mx -all" in Exchange Server 2003 (921291)

SYMPTOMS

Consider the following scenario. You create a Sender of Policy Framework (SPF) record in Microsoft Windows Server 2003 Domain Name System (DNS). You enable Sender ID Filtering on a Simple Mail Transfer Protocol (SMTP) virtual server in Microsoft Exchange Server 2003 Service Pack 2 (SP2). In this scenario, the Sender ID filter may reject e-mail that is sent from an IP address that is associated with an SPF record that contains the following text:

v=spf1 mx -all

RESOLUTION

Hotfix information

A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Only apply it to systems that are experiencing this specific problem. This hotfix may receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next Exchange Server 2003 service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the hotfix. For a complete list of Microsoft Product Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:

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

Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

Prerequisites

You must have Exchange Server 2003 SP2 installed to apply this hotfix.

Restart requirement

You do not have to restart the computer after you apply this hotfix. However, Microsoft Internet Information Services (IIS) Admin Service and all dependent services are stopped and then restarted when you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfix.

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 item in Control Panel.

File name	File version	File size	Date	Time	Platform
Msgfilter.dll	6.5.7651.38	207,360	26-Jul-2006	16:44	x86

MORE INFORMATION

Notes

After you apply this hotfix, you may notice a small increase in DNS query traffic.
MX records must not point to CNAME records.

For more information about how to configure Sender of Policy Framework records in the Windows Server 2003 Domain Name System, click the following article number to view the article in the Microsoft Knowledge Base:

912716 How to configure Sender of Policy Framework records in the Windows Server 2003 Domain Name System

For more information, click the following article numbers to view the articles in the Microsoft Knowledge Base:

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

817903 New naming schema for Exchange Server software update packages