Outlook message data is sent over the network unexpectedly (908625)


The information in this article applies to:

  • Microsoft Office Outlook 2003
  • Microsoft Outlook 2000
  • Microsoft Outlook 2002

SYMPTOMS

When you work with e-mail messages in Microsoft Outlook, attachment or e-mail message data may be sent over the network unexpectedly. In this situation, you experience the following symptoms:
  • Performance may be reduced when the data for very large attachments is sent over the network.
  • The e-mail message or attachment data that is sent over the network is not encrypted if RPC encryption is not enabled for the e-mail profile.

CAUSE

This behavior occurs because the Microsoft Exchange Server store provider (Emsmdb32.dll) that is used for communication between Outlook and the Exchange store purposefully sends data to and from the server for various reasons. The Exchange store provider may perform in this manner to increase performance or to enable features in Outlook. All the scenarios in which data is sent over the network may not be expected or considered necessary by a user. However this behavior is necessary for the Exchange store provider. This behavior is part of the current design for MAPI clients and the store provider. Therefore, this should be considered an expected behavior.

MORE INFORMATION

Exchange client extensions that interact with Outlook e-mail messages may be specifically exposed to this design. When these client extensions intercept and handle events such as Onread and Onwrite to work with the data, the extension may not expect data to be sent over the network. However, data is sent over the network by design. Because this is part of the fundamental design of MAPI clients and the store provider, there is no easy way to prevent the data from being sent over the network.

Note By default, data that is sent over the network is encoded. However, the data that is described in this article not encrypted. You must enable RPC encryption for the Outlook profile if security is a concern in your organization.

STATUS

This behavior is by design.
Modification Type:MajorLast Reviewed:3/20/2006
Keywords:kbnofix kbinfo kbnetwork kbtshoot kbprb KB908625 kbAudITPRO
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