Private Sub Worksheet_Calculate()
Dim col As Byte
For col = 14 To 73 'colonnes N à BU
If cells(874, col) = 0 And cells(877, col) <> 0 Then
MsgBox "This press has volume loaded...You can't have that Press inactive, unless you remove the volume "
[COLOR="Red"]On Error Resume Next
Application.EnableEvents = False
Application.Undo
Application.EnableEvents = True[/COLOR]
Exit For
End If
Next
End Sub