Microsoft KB Archive/161945

From BetaArchive Wiki

Article ID: 161945

Article Last Modified on 10/28/2006



APPLIES TO

  • Microsoft Exchange Server 4.0 Standard Edition
  • Microsoft Exchange Server 5.0 Standard Edition



This article was previously published under Q161945


SYMPTOMS

When you are using the Microsoft Mail client or the Microsoft Exchange Client connected to a Microsoft Mail postoffice, file attachments included in messages from Internet users contain blank icons. This is true even for icons that are associated with programs on the local computer. The document does open correctly when it is clicked, if an associated program exists for the attachment.

For example, your Microsoft Mail client shows a blank icon for an attached Microsoft Word document, even though you have Word installed. Double- clicking the blank icon starts Word (if it is not already started), and the document opens correctly in Word.

CAUSE

Microsoft Mail clients display icon images according to the following algorithms:

Winmail.dat File Does Not Exist

If an e-mail message has an attachment, and no Winmail.dat file, the mail client will display an icon for the file if an association for the file extension has been established. The Winmail.dat file is a special file created by Microsoft Mail clients that contains MAPI property information, rich-text formatting, icon images, and other non-text related items.

Winmail.dat File Does Exist

If an e-mail message has an attachment and a Winmail.dat file, the mail client will display the icon image present in the Winmail.dat file. The Winmail.dat file always contains an icon image for each attachment.

When mail from the Internet Mail Connector (IMC) is passed to the Microsoft Mail Connector interchange (MSMI), the MSMI always projects a Winmail.dat file for any message that contains an attachment. Because the original message received by the MSMI may not contain an icon image (if it originated from a client other than Microsoft Mail), the MSMI inserts a blank icon image into the Winmail.dat file.

Because the Microsoft Mail client sees a Winmail.dat file (created by the MSMI), it expects an icon image to be present.

WORKAROUND

Use either of the following methods:

Method 1: Migrate Users

Migrate users to the Microsoft Exchange Client using Microsoft Exchange Server as their message store. In this standard configuration, Microsoft Exchange clients will display an icon if present from the sender. If no icon is present, the client will display an icon associated with the file based on its associations.

Method 2: Use the Fix Described

The Status section of this article describes a fix that is available from Microsoft Technical Support.


STATUS

Microsoft has confirmed this to be a problem in Microsoft Exchange versions 4.0 and 5.0. This problem was corrected in the latest Microsoft Exchange Server 4.0 and 5.0 U.S. Service Packs. For information on obtaining the service pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

S E R V P A C K


MORE INFORMATION

To operate, the fix requires that the Microsoft Exchange Server computer that is running the Microsoft Mail Connector interchange (MSMI) must be running Microsoft Windows NT 4.0. In addition, the fix works by allowing the MSMI to provide an icon image for documents (instead of using a blank icon image). For the fix to work, the applications for the documents that are received as blank icons must be installed on the Microsoft Exchange Server computer with the fix. (That is, you must install Microsoft Word for Windows on the Microsoft Exchange server, if .doc files are received with blank icons.)

WARNING: Using Registry Editor incorrectly can cause serious, system-wide problems that may require you to reinstall Windows NT to correct them. Microsoft cannot guarantee that any problems resulting from the use of Registry Editor can be solved. Use this tool at your own risk.

  • To activate the fix, you must add a value to the registry:

    Edit the registry key as follows:

          HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services
             \MSExchangeMSMI\Parameters
                            

    Add the following registry value (type of DWORD set to 1):

          Search for icon on server

If this registry entry is present and the value is set to 1, the MSMI will search the Windows NT registry of the server that it is running on to locate an executable file that contains the icon for the associated extension of the attachment file name.

If this registry entry is not present, the default value is FALSE or 0. In this case, the MSMI will use the default icon for attachments in a message that do not already have an icon image. This is normal behavior of the MSMI.

For additional information about Winmail.dat, please see the following article in the Microsoft Knowledge Base:

136204 XCLN: Sending Messages in Rich-Text Format


Keywords: kbbug kbfix KB161945