Why can't I open my DSLR Canon 7D on this Trial Version?
According to the information found on the Supported Cameras page, the Canon 7D is supported. In this case, I recommend checking the camera's installation on PC, then download the latest version of the software from the official website. Make sure to run the installation and the application as Administrator. This will give access to software to detect the attached peripherals.
Download page: http://www.photoboothsolutions.com/socialbooth/#
