[Митяй2]

Ошибка оказывается возникает в модуле Forms.pas !!!!:

ЗДЕСЬ: if FControl.FAutoScroll then

Код:

procedure TControlScrollBar.CalcAutoRange;
var
  I: Integer;
  NewRange, AlignMargin: Integer;

  procedure ProcessHorz(Control: TControl);
  begin
    if Control.Visible then
      case Control.Align of
        alLeft, alNone:
          if (Control.Align = alLeft) or (Control.Anchors * [akLeft, akRight] = [akLeft]) then
            NewRange := Max(NewRange, Position + Control.Left + Control.Width);
        alRight: Inc(AlignMargin, Control.Width);
      end;
  end;

  procedure ProcessVert(Control: TControl);
  begin
    if Control.Visible then
      case Control.Align of
        alTop, alNone:
          if (Control.Align = alTop) or (Control.Anchors * [akTop, akBottom] = [akTop]) then
            NewRange := Max(NewRange, Position + Control.Top + Control.Height);
        alBottom: Inc(AlignMargin, Control.Height);
      end;
  end;

begin
  if FControl.FAutoScroll then
  begin
    if FControl.AutoScrollEnabled then
    begin
      NewRange := 0;
      AlignMargin := 0;
      for I := 0 to FControl.ControlCount - 1 do
        if Kind = sbHorizontal then
          ProcessHorz(FControl.Controls[i]) else
          ProcessVert(FControl.Controls[i]);
      DoSetRange(NewRange + AlignMargin + Margin);
    end
    else DoSetRange(0);
  end;
end;

TControlScrollBar.CalcAutoRange вызывается в:

Код:

procedure TScrollingWinControl.WMSize(var Message: TWMSize);
var
  NewState: TWindowState;
begin
  Inc(FAutoRangeCount);
  try
    inherited;
    NewState := wsNormal;
    case Message.SizeType of
      SIZENORMAL: NewState := wsNormal;
      SIZEICONIC: NewState := wsMinimized;
      SIZEFULLSCREEN: NewState := wsMaximized;
    end;
    Resizing(NewState);
  finally
    Dec(FAutoRangeCount);
  end;
  FUpdatingScrollBars := True;
  try
    CalcAutoRange;
  finally
    FUpdatingScrollBars := False;
  end;
  if FHorzScrollBar.Visible or FVertScrollBar.Visible then
    UpdateScrollBars;
end;