You can configure the Trouble Ticketing System and Enable/Disable it from this page.
The light bulb icon indicates the state of Trouble Ticketing System, click it to toggle the TTS on or off.
To enable the Trouble Ticketing System you also need to specify an arbitrary server id for identification in the Server id field, enable the Allow customers to submit tickets checkbox, and select the default queue, priority and category. Click OK. Now clients, domain owners, and mailbox users can submit the trouble tickets to the TTS.