Creating a NetDDE Link in Excel on Windows NT

Because of changes in the Clip Book format and OLE, Clipbook can no longer be used to create Network DDE Links between Excel Worksheets. This article provides step by step instructions for creating Network DDE Links for Excel using the Network DDE Share Manager.

A Network DDE Link consists of two parts; the DDE server application and the DDE client application. The DDE server application contains the data to be shared. The DDE client requests the data from the DDE server, thus creating a DDE Link. Network DDE requires the server application to make the data accessible on the network. The server Application creates a Network DDE share, available over the network, which the client application can connect to.

In Windows NT 3.1, Clipbook could be used to create the Network DDE share. In version Windows NT 3.5, because of changes to the ClipBook and OLE, the ClipBook can no longer be used to create Network DDE Links for Excel worksheets.

To create a Network DDE link under Windows NT 3.5:

1. Use DDE Share Manager (%SYSTEMROOT%\SYSTEM32\DDESHARE.EXE) to create a share on the DDE server:
   
   
   1. Select Add a Share in the SHARES.DDESHARES menu.
   2. Enter a share name. The share must end with a dollar sign ($), for example SalesData$.
      
      NOTE: This share is not a directory. You cannot see it in File Manager.
   3. Under Application Name, enter the following:
      
      

            Old Style:  Excel
            New Style:  Excel.Sheet.5
            Static:
      
            NOTE: Leave Static blank.

   4. Under Topic Name, enter the following:
      
      

            Old Style:  [SALES.XLS]Sheet1   - This is the File Name and the
                                              Worksheet name
            New Style:  SALES.XLS           - This is the File Name
            Static:
      
            NOTE: Leave Static blank.

   5. Select Allow Start Application.
   6. Choose Permissions and then set permissions for the share the same way you would set permissions on files using File Manager.
   7. Choose OK.
   8. Select the share you just created and choose Trust Share.
   9. Choose Set and then choose OK.
2. Launch Excel on the server and create or open a workbook named "SALES.XLS," with a sheet named "Sheet1." It does not matter what directory SALES.XLS is saved to. Enter something into cell A1 (it does not matter what you enter).
3. Create a link to the share that you just created.
   
   This example uses the share name SalesData$ and the DDE server machine \\MARLEY. The workbook name is SALES.XLS and the data to be linked is in SHEET1, column 1, row 1.
   
   
   1. At the DDE client machine, run Excel.
   2. Enter the following command into the first cell:
      ='\\MARLEY\NDDE$'|'SalesData$.OLE'!'Sheet1!R1C1'
      NOTE: You may be prompted for a password. If so, enter a valid user account and password which exists in the DDE server's domain or a trusted domain.
4. The linked data should appear in the cell when you press enter. If the cell shows "N/A", choose Links from the Edit menu. The link should be listed as follows:
   
   

         Source File:  SalesData$.OLE
         Item:         Sheet1!R1C1
         Type:         \\MARLEY\NDDE$
         Status:       Automatic
   						

   To update the link, select Update Now. The link updates, and the data is linked to the client workbook. The link may not update in Excel on the existing client. If the link does not update, press F2 and then press ENTER to edit the cell. When you edit the cell, be aware of the following:
   • If you do not save the Excel workbook that is on the server in the My Documents folder or in the Winnt\profiles\user\personal folder, provide the absolute path in the file name, such as C:\SALES.XLS.
     
     Note Winnt\profiles\user\personal is the default location where Excel saves files.
   • If you move the Excel workbook that is on the server, you change the share configuration. Therefore, you must explicitly trust the new share version. To do this, open the Trusted Share Properties dialog box, and then click Set.

To run NetDDE programs in Windows 95, you must add a shortcut for Netdde.exe to the Startup group. To do so, follow these steps:

1. Right-click an empty space on the taskbar, and then click Properties.
2. On the Start Menu Programs tab, click Add.
3. Use the Create Shortcut Wizard to create a shortcut for Netdde.exe in the Windows folder.
4. After you create the shortcut, restart your computer.

NOTE: With Excel 97, use "Excel.Sheet.8" for the New Style Application name. Also, with Excel versions 7.0, 7.0a, and Excel 97, check "Start Application Enable" and "Initiate to Application Enable" check boxes in the Trusted Share Properties dialog box.