XL 2016 Macro si cellules vides

    If Not Intersect(Target, Range("F34:N" & Cells(Rows.Count, "A").End(xlUp).Row)) Is Nothing Then
        If WorksheetFunction.CountIf(Rows(Target.Row).Columns("A:E"), "<>") = 4 Then
            If WorksheetFunction.CountIf(Rows(Target.Row).Columns("F:N"), "<>") < 9 Then
                If Range("P" & Target.Row) = "" Then
                    Application.EnableEvents = False
                    Z = Application.InputBox("Un commentaire est obligatoire" & vbLf & "pour cette ligne")
                    If Not Z = False Then Range("P" & Target.Row) = Z
                    Application.EnableEvents = True
                End If
            End If
        End If
    End If

Private Sub Workbook_BeforeClose(Cancel As Boolean)
    If Not ThisWorkbook.Saved Then
        Select Case MsgBox("Voulez-vous enregistrer ce Classeur ?", vbQuestion + vbYesNoCancel)
        Case vbYes: ThisWorkbook.Save
        Case vbCancel: Cancel = True
        Case vbNo: ThisWorkbook.Saved = True ' On quitte sans sauvegarder
        End Select
    End If
End Sub

Private Sub Workbook_BeforeSave(ByVal SaveAsUI As Boolean, Cancel As Boolean)
Dim Ligne As Range
    For Each Ligne In Range("A34:S" & Cells(Rows.Count, "A").End(xlUp).Row).Rows
        If WorksheetFunction.CountIf(Ligne.Columns("F:N"), "<>") < 9 Then
            If Ligne.Columns("P") = vbNullString Then
                Z = Application.InputBox("Un commentaire est obligatoire" & vbLf & "pour le n°Of " & Ligne.Columns("D"))
                If Not (Z = False Or Trim(Z) = vbNullString) Then
                    Application.EnableEvents = False
                    Ligne.Columns("P") = Z
                    Application.EnableEvents = True
                Else
                    Cancel = True
                    Exit For
                End If
            End If
        End If
    Next
    If Not Cancel Then ThisWorkbook.Save
End Sub

    If Not Intersect(Target, Range("F34:N" & Cells(Rows.Count, "A").End(xlUp).Row)) Is Nothing Then
        If WorksheetFunction.CountIf(Rows(Target.Row).Columns("A:E"), "<>") = 4 Then
            If WorksheetFunction.CountIf(Rows(Target.Row).Columns("F:N"), "<>") < 9 Then
                If Range("P" & Target.Row) = "" Then
                    Application.EnableEvents = False
                    Z = Application.InputBox("Un commentaire est obligatoire" & vbLf & "pour cette ligne")
                    If Not Z = False Then Range("P" & Target.Row) = Z Else Target.ClearContents
                    Application.EnableEvents = True
                End If
            End If
        End If
    End If