If you right-click on your Toolbox window and select "Reset Toolbox". That will return the Toolbox to stock in case you have deleted the component. This will remove any custom ones you've added, so be aware of that.
You may also simply add it back. To do so, right-click on your Toolbox window (I would do so under the Advanced section as that is where this component lies normally) and select "Choose Items". When the window opens, select the ".Net Framework Components" tab. In the "Filter" box, enter "AsoManager" and you should see the component. If you place a check in the CheckBox and click "OK", then it should appear in your Toolbox.