Option Explicit

Private Const sPASSWORD     As String = "Passwort"
Private bCellDragAndDrop    As Boolean

Private Sub Workbook_Open()
  Dim objWks As Worksheet

  On Error GoTo ErrPassword
  For Each objWks In ThisWorkbook.Worksheets
    With objWks
      .Unprotect Password:=sPASSWORD
      .EnableOutlining = True
      .Protect Password:=sPASSWORD, UserInterfaceOnly:=True
    End With
  Next objWks

  ThisWorkbook.Saved = True
  Exit Sub

ErrPassword:
  MsgBox "Ein unbekannter Fehler ist aufgetreten!" & _
      String(2, vbCr) & "Quelle" & vbTab & Err.Source & vbCr & _
      "Fehler" & vbTab & Err.Description, vbCritical, _
      "Fehler-Nr. " & Err.Number
End Sub

Private Sub Workbook_Activate()
  bCellDragAndDrop = Application.CellDragAndDrop
  Application.CellDragAndDrop = False
End Sub

Private Sub Workbook_Deactivate()
  Application.CellDragAndDrop = bCellDragAndDrop
End Sub

Private Sub Workbook_SheetBeforeRightClick(ByVal Sh As Object, _
      ByVal Target As Range, Cancel As Boolean)
  Change_Group Sh, Target.EntireColumn, Cancel
End Sub

Private Sub Workbook_SheetBeforeDoubleClick(ByVal Sh As Object, _
      ByVal Target As Range, Cancel As Boolean)
  Change_Group Sh, Target.EntireRow, Cancel
End Sub

Private Sub Change_Group(ByRef rSh As Object, _
      ByRef rRng As Range, ByRef rbCancel As Boolean)

  If TypeOf rSh Is Worksheet Then
    On Error GoTo ErrWrongPassword
    rSh.Unprotect Password:=sPASSWORD
    On Error Resume Next

    rRng.ShowDetail = Not rRng.ShowDetail
    If Err.Number = 0 Then
      rbCancel = True
    End If

    rSh.Protect Password:=sPASSWORD, UserInterfaceOnly:=True
  End If

ErrWrongPassword:
End Sub