In a Microsoft Exchange Server environment, a user sends an email message that has one or more inline attachments. When the recipient receives the message, it does not contain any inline attachments. Instead the message contains one or more attachments. These attachments may include text files that contain text content from the original body of the message.
If the recipient or sender is external to the Exchange organization, you can enable pipeline tracing to view a snapshot of the message as it's received by Exchange. Analysis of the message shows the correct boundary being used within separate parts of the message. However, the section that contains the message text uses the Content-Type of text/plain. Exchange uses this value to determine the format of the message and in this scenario uses the Plain Text format, which cannot display inline images. Therefore, each section is added as a separate attachment to the message.
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