Sets the Windows registry value that determines the default application used to activate the specified OLE object.
expression.ActivateAs(ClassType)
expression Required. An expression that returns an OLEFormat object.
ClassType Required String. The name of the application in which an OLE object is opened. To see a list of object types that the OLE object can be activated as, click the object and then open the Convert dialog box (Edit menu, Object submenu). You can find the ClassType string by inserting an object as an inline shape and then viewing the field codes. The class type of the object follows either the word "EMBED" or the word "LINK."
Example
This example sets the first floating shape on the active document to open in Microsoft Excel, and then it activates the shape. For the example to work, this shape must be an OLE object that can be opened in Microsoft Excel.
With ActiveDocument.Shapes(1).OLEFormat
.ActivateAs ClassType:="Excel.Sheet"
.Activate
End With