First, you need to close all the Application that is using the Camera. Please right click on the "Camera" icon on the right side of the Taksbar and click the "Exit" . After that, please open the "WebCam Companion" Sofware and then try clicking the "connect" button.
If the issue still perists, please uninstall and re-install the Webcam Companion Software in the Computer to resolve the issue. Please make sure that you restart the Computer after uninstalling the Webcam Companion Software. Then, please download the Software from Sony Support Site and re-install it in the Computer.
You can download the WebCam Companion Software from here.
Download the file and save it in a folder in the Computer. Then, open the folder where the file is saved and double click on it to begin the installation. Then, please follow the on screen instructions to complete the installation process.
Re-installing the Webcam Companion Sottware should fix it.
Best of luck....