It's possible that when you installed the program, you agreed that it will start when the computer starts. In this case, even if you close it, there will be an instance that is running. To overcome this problem, go to Start > Run > msconfig and press Enter. In the new window, go under the Service tab and make sure to select the Hide all Microsoft services option from the bottom of the page. Next, go to the Startup tab, and uncheck any services that are related to Astaro SSL VPN. After you did this, reboot your computer. You will be able to create a new connection. If you still receive the same error message, press the Ctrl + Shift + Esc key combination to open the Task Manager, go under the Process tab, and close any process that is related to the mentioned product. You should be able to overcome these problems.