Sub ColourChange()
With ActiveDocument.Content.Find
  .ClearFormatting
  .Text = "FQCN73"
  With .Replacement
    .ClearFormatting
    .Text = "^&"
    .Font.Color = wdColorRed
  End With
  .Forward = True
  .Wrap = wdFindContinue
  .Format = True
  .MatchCase = False
  .MatchWholeWord = False
  .MatchWildcards = False
  .MatchSoundsLike = False
  .MatchAllWordForms = False
  .Execute Replace:=wdReplaceAll
End With
End Sub