Exchange Server 2003 does not include the "In-reply-to" header field when you use Outlook or Outlook Web Access to reply to an e-mail message that originated from outside the organization

Microsoft Exchange Server 2003 does not add the In-reply-to header field when you reply to an e-mail message that originated from outside the organization. This problem occurs when you send the reply by using Microsoft Outlook or Microsoft Outlook Web Access. Additionally, this problem occurs when one of the following conditions is true:

• Outlook is configured in MAPI mode.
• Outlook Web Access is used without the Secure/Multipurpose Internet Mail Extensions (S/MIME) control.
  
  Note To use S/MIME, you must configure Exchange Server 2003 after you install the S/MIME control on the client computer.

Note The In-reply-to header field typically contains the message ID of the e-mail message to which you reply. The In-reply-to header field is used by some messaging programs to identify the reply as part of an e-mail thread.

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: 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

You must install Microsoft Exchange Server Service Pack 2 (SP2) or Microsoft Exchange Server 2003 Service Pack 1 (SP1) before you apply this hotfix.

Restart requirement

You do not have to restart the computer after you apply the hotfix. However, the Microsoft Exchange Information Store service and all dependent services will be restarted.

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.

Microsoft Exchange Server 2003 SP2Microsoft Exchange Server 2003 SP1

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

Exchange Server 2003 correctly adds the In-reply-to header field in some client configurations. The following table summarizes the circumstances under which the In-reply-to header field is included.
For more information, click the following article number to view the article in the Microsoft Knowledge Base: For more information, click the following article number to view the article in the Microsoft Knowledge Base:

For more information about how to install the S/MIME control or how to configure Exchange Server 2003 to use S/MIME for Outlook Web Access, click the following article number to view the article in the Microsoft Knowledge Base: