You receive an NDR message after you send an e-mail message that contains a .zip file attachment by using an Exchange 2007 Edge server

After you send an e-mail message by using a Microsoft Exchange Server 2007 Edge server, you receive a non-delivery report (NDR) message that includes the following information:This problem occurs if the following conditions are true:

• The e-mail message contains a .zip file attachment.
• The Attachment Filtering agent is enabled on the Exchange 2007 Edge server.

If you enable tracing for Exchange 2007, an exception exists. This exception indicates that the .zip file attachment is invalid. However, you can correctly open the attached .zip file.

This problem occurs because the Attachment Filtering agent cannot correctly parse certain .zip files. In these .zip files, the compressed size is not computed and then set before the file data.

To resolve this problem, install Update Rollup 5 for Exchange Server 2007.

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

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