A Microsoft Exchange Server 2007 user accesses a mailbox by using a third-party mail client.
The user sends an email message where the body of the email message resembles the following: <text> <graphic> <text>
A recipient opens this email message by using Microsoft Office Outlook.
In this scenario, the body of the email message only includes the first "<text>" part, the "<graphic>" and other "<text>" parts are displayed as attachments.
This issue occurs because the third-party mail client sends the email message in Multipurpose Internet Message Encoding (MIME) format. The body of this email message is multipart/mixed content type. However, Exchange Server 2007 processes this kind of message body into independent parts. Therefore, the attachments are created for different parts of the email message body.
To resolve this issue, install the following update rollup:
2530488 Description of Update Rollup 3 for Exchange Server 2007 Service Pack 3
After you apply this update, Exchange Server 2007 merges the parts of the multipart/mixed content type message into one body when the email message is sent by certain third-party mail clients.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.