Function ValComment(S As String, Rng As Range) As String
Dim Cell As Range
For Each Cell In Rng
If InStr(1, Cell.Value, S, vbTextCompare) Then
If InStr(1, Cell.Comment.Text, S, vbTextCompare) Then
ValComment = Cell.Address(0, 0)
Exit Function
End If
End If
Next
End Function