If, while trying to add the terminal in the software, it gives us an error saying that the terminal is already added to the application when it really is not, this can be solved in the following way:
1) If we have 2 storage hard disks, perform again the installation of the program in the D hard disk (the issue is in fact related to the user permissions within the C disk)
2) Always run the program as an administrator.
3) If following all the previous steps the problem persists, finally we would have to make sure that the firewall of our operating system and the firewall of the antivirus are deactivated.