Trial
You are able to use all VisualCron functions for free for a limited period (30 days). Check the remaining trial days in the main menu About -> About VisualCron dialog. After the trial period is over, you can't control the server with the client. However, the server will still run all Jobs in the background even though your trial period is over. To be able to manage your Jobs again you must obtain a license.
If you want to extend you trial period you can contact support@visualcron.com and you will get a trial extension code. Enter the trial extension code in Client->Server tab->License->Activate and Trial extension tab.