Update Method
Updates the specified linked OLE object. To update all the links in a presentation at once, use the UpdateLinks method.
expression.Update
expression Required. An expression that returns a LinkFormat object.
Example
This example updates all linked OLE objects in the active presentation.
For Each sld In ActivePresentation.Slides
For Each sh In sld.Shapes
If sh.Type = msoLinkedOLEObject Then
sh.LinkFormat.Update
End If
Next
Next