This code highlights duplicate values in the selected range.
VBA Code:
Sub HighlightDuplicates()
Selection.FormatConditions.AddUniqueValues
Selection.FormatConditions(Selection.FormatConditions.Count).SetFirstPriority
Selection.FormatConditions(1).DupeUnique = xlDuplicate
With Selection.FormatConditions(1).Font
.Color = -16383844
.TintAndShade = 0
End With
With Selection.FormatConditions(1).Interior
.PatternColorIndex = xlAutomatic
.Color = 13551615
.TintAndShade = 0
End With
Selection.FormatConditions(1).StopIfTrue = False
End Sub