Private Sub Worksheet_Change(ByVal Target As Range)
Application.ScreenUpdating = False
Application.EnableEvents = False
With ActiveSheet
y_max = .Range("A1").CurrentRegion.Rows.Count
x_max = .Range("A1").CurrentRegion.Columns.Count
For y = 1 To y_max
For x = 1 To x_max
If .Cells(y, x) = "DUE" Then
If WorksheetFunction.Find("IF", .Cells(y, x).Formula, 1) > 0 Then
' Write here Your code to send email...
End If
End If
Next x
Next y
End With
Application.EnableEvents = True
Application.ScreenUpdating = True
End Sub