E-mail messages may not be delivered when you use the "Filter messages with blank sender" option in Exchange Server 2003

When you use the Filter messages with blank sender option in Microsoft Exchange Server 2003, messages may be incorrectly filtered. When this problem occurs, some e-mail messages that do have a sender may not be delivered.

This problem occurs if one of the following conditions is true:

• The From field of the e-mail message contains a comment.
• The From field of the e-mail message contains a space character from a single-byte character set. This space character is between characters from a double-byte character set.

Service pack information

To resolve this problem, obtain the latest service pack for Windows Server 2003. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

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

No prerequisites are required.

Restart requirement

You must restart your computer after you apply this hotfix.

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.

Windows Server 2003, 32-bit editions

Windows Server 2003, Enterprise Edition for Itanium-based Systems

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section. This problem was first corrected in Windows Server 2003 Service Pack 2.

In a single-byte character set, each character is represented by one byte. In a double-byte character set, a character can use more than one byte. A double-byte character set includes characters that use one byte and characters that use two bytes. Languages such as Chinese, Japanese, and Korean use double-byte character sets.

For additional information about how to resolve this problem if you are running Microsoft Exchange 2000 Server, click the following article number to view the article in the Microsoft Knowledge Base: For additional information about the terminology that is used in this article, click the following article number to view the article in the Microsoft Knowledge Base: