An e-mail message that you send is corrupted when the subject line of an attached e-mail message matches one or more file filters that you configured in Forefront Security for Exchange Server

If you send a Microsoft Office Outlook e-mail message that has another e-mail message attached, Microsoft Exchange Server uses the subject line of the attached e-mail message as the file name for the attached e-mail message. If the subject line of the attached e-mail message ends in a file name extension, the subject line of the attached e-mail message may match one or more file filters that you configured in Microsoft Forefront Security for Exchange Server. In this case, Forefront Security for Exchange Server tries to delete and to quarantine the e-mail message that you send because of the file filter settings. When this problem occurs, the e-mail message that you send is corrupted and is not delivered to the recipient. You receive a non-delivery report that resembles the following:For example, in Forefront Server Security Administrator, you configure a file filter that searches for a file name that has the .com extension. Additionally, you configure the file filter to delete and to quarantine any e-mail messages that it detects. Then, you send an e-mail message through the server. The e-mail message that you send has another e-mail message attached. The subject line of the attached e-mail message is as follows: Exchange Server uses this subject line as the file name for the attached e-mail message. Therefore, the .msg extension is not appended to the file name for the attached e-mail message. Because the file name for the attached e-mail message has the .com extension, Forefront Security for Exchange Server matches the file filter that you configured to the attached e-mail message. Then, this problem occurs.

To resolve this problem, you must install Hotfix Rollup 3 for Forefront Security for Exchange Server Service Pack 1. For more information, click the following article number to view the article in the Microsoft Knowledge Base: Note Forefront Security for Exchange Server Service Pack 1 must be installed before you install this hotfix rollup.

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