How to Stop Word from Opening Every Document Separately?

This feature is hard-wired into Word. So, though you can’t directly stop it, i.e. through the menu options, we have some macros that work around it. 

Macro to Update all Fields in a Document

The code is as follows:
  Sub UpdateAll()
   Dim oStory As Range
   Dim oField As Field
   On Error Resume Next
 For Each oStory In ActiveDocument.StoryRanges
 For Each oField In oStory.Fields
 oField.Update

 Next oField
 Next oStory
   On Error GoTo 0
   End Sub

1. Select Tools, Macro, Create New Macro.
2. Name the macro.