You cannot use an Outlook 2010 client or an Outlook 2007 client to display or download an attachment when you access a message that includes an inline attachment from Microsoft Exchange Server

Applies to: Exchange Server 2010 EnterpriseExchange Server 2010 Standard


Consider the following scenario. A MIME-encoded message that includes an inline attachment arrives in Microsoft Exchange Server. You try to access the message from a Microsoft Outlook 2010 or Microsoft Office Outlook 2007 client. In this scenario, the attachment is hidden, and it is unavailable for download. If you use Microsoft Office Outlook Web Access to view the same message, the inline attachment is still hidden. However, the inline attachment is available for download in Outlook Web Access, and you can click the message and view it.


This issue occurs when Exchange Server does not validate whether there is a reference to the inline attachment. If the inline attachment is not referenced, the inline attachment is hidden.


Exchange Server 2010

  1. Stop the Exchange Transport service.
  2. Locate the EdgeTransport.exe.config file. This file is located in the following path:
    <drive> :\Program Files\Microsoft\Exchange Server\Bin\
  3. In the EdgeTransport.exe.config file, add the following entry between the <appSettings> element and the </appSettings> element:
    <add key="TreatInlineDispositionAsAttachment" value="true" />
  4. Restart the Transport service.
  • You must have Exchange Server 2010 RTM Rollup Update 4 (RU4) installed for the new entry in the EdgeTransport.exe.config file to take effect.
  • If the TreatInlineDispositionAsAttachment option does not exist or if the option is set to "false," the behavior is the same as the behavior that is mentioned in the "Symptoms" section.
  • If the TreatInlineDispositionAsAttachment option is set to "true," the inline attachment that is not referenced is available for download.

Exchange Server 2007

  1. Make sure that Exchange Server 2007 Service Pack 2 is installed.
  2. Run the following command:
    set-OrganizationConfig -ShowInlineAttachments:$true

More Information

For more information about a similar issue that is specific to Outlook 2003, click the following article number to view the article in the Microsoft Knowledge Base:
930468 The attachment is not displayed when you use Outlook 2003 to open an e-mail message that contains an attachment

For more information about RFC2183, visit the following Web site:For more information about RFC2387, visit the following Web site:For more information about the set-OrganizationConfig command, visit the following Web site:


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