Hi zkid,

Have you tried this? It's not an error; you can't trap it.

The message can be suppressed with DisplayAlerts None but the question was
"Why", not "How do I get round it?" - and, yes, Word does have some unruly
children and that may be the only answer.

zkid,

There is nothing at all wrong to update all of the fields in a document.
That is exactly what I was doing when I first encountered this issue.  I was
using the code shown below to
to update all the fields in a document as part after certain bookmarks where
defined in a Userform.  I had never had a REF field in a footnote before and
was surprised by the alert that popped up.

I admit that PrintPreview and ClosePrintPreview is a quick and, as far as I
know, efficient way to update fields. I just don't normally use it because
sometimes there are other things that I might want to do with fields.

Sub myUpdateFields()
Dim rngStory As Word.Range
Dim oShp As Word.Shape
For Each rngStory In ActiveDocument.StoryRanges
 Do
   On Error Resume Next
    rngStory.Fields.Update
    Select Case rngStory.StoryType
       Case 6, 7, 8, 9, 10, 11
         If rngStory.ShapeRange.Count > 0 Then
           For Each oShp In rngStory.ShapeRange
             If oShp.TextFrame.HasText Then
               oShp.TextFrame.TextRange.Fields.Update
             End If
           Next oShp
         End If
       Case Else
         'Do Nothing
      End Select
    On Error GoTo 0
    'Get next linked story (if any)
    Set rngStory = rngStory.NextStoryRange
  Loop Until rngStory Is Nothing
Next rngStory
End Sub

As Tony mentions, this post wasn't to find out how to stop the alert from
appearing but a question as to why it appears.