Salut abdernino, ric,
A coller dans le module de la feuille concernée.
La macro réagit aux changements dans les colonnes [B:J].
Private Sub Worksheet_Change(ByVal Target As Range)
'
Application.ScreenUpdating = False
'
If Not Intersect(Target, Range("B:J")) Is Nothing And Target.Row >= 10 Then
iTRow = IIf(Target.Count = 1, Target.Row, Target.Row + Target.Rows.Count - 1)
For x = 2 To 10
iRow = IIf(Range(Chr(64 + x) & Rows.Count).End(xlUp).Row > iRow, Range(Chr(64 + x) & Rows.Count).End(xlUp).Row, iRow)
Next
If iTRow > iRow Then Range("B10:J" & iTRow).Borders.LineStyle = xlLineStyleNone
Range("B" & IIf(iRow < 10, 9, 10) & ":J" & iRow).Borders.LineStyle = xlContinuous
End If
'
Application.ScreenUpdating = True
'
End Sub
A+