sharonm was telling us:
sharonm nous racontait que :

If you are talking about a protected form, you do not need VBA.

Just make sure that you check the "Calculate on Exit" check box in the
formfield properties (by right clicking on the formfield "ContactName")

By the way, activating the Hyperlink option in a protected form is useless
as it will not work when the document is protected.

This code works on both protected and unprotected documents.  If you want,
you can leave out the error-checking, but it's handy to let you know if one
of your cross-references no longer has a valid hyperlink:

On Error GoTo ErrorHandler
   ActiveDocument.PrintPreview
   ActiveDocument.ClosePrintPreview

StatusBar = "Updating fields - please wait..."

Exit Sub

ErrorHandler:

If ActiveDocument.Fields.Update <> 0 Then
   MsgBox "Field " & ActiveDocument.Fields.Update & _
       " has an error - please check for missing bookmark codes", _
          vbInformation, "Updated Fields Prompt"
End If