Private Sub Workbook_Activate()
Application.Visible = False 'Visible=True предусмотрел! :)
frmCheck.Show
End Sub

Private Sub UserForm_QueryClose(Cancel As Integer, CloseMode As Integer)
   With Application: .ActiveWorkbook.Close: .Quit:  End With
End Sub

Private Sub Workbook_BeforeClose(Cancel As Boolean)
    With Application: .EnableEvents = False: .DisplayAlerts = False
    If Not Me.Saved Then Me.Save
    .EnableEvents = True: .DisplayAlerts = True:  End With
End Sub

 Application.Quit

.ActiveWorkbook.Close

 Private Sub Workbook_BeforeClose

.Quit

:Private Sub Workbook_BeforeClose(Cancel As Boolean)
    With Application: .EnableEvents = False: .DisplayAlerts = False
    If Not Me.Saved Then Me.Save
    .Quit
    .EnableEvents = True: .DisplayAlerts = True:  End With
End Sub

.Quit

 .Quit

 ? Application.DisplayAlerts