I have used this webcam before and it worked fine. The program, application, or website, turned the camera on. It's a Windows 7 desktop. When inserted in the front USB port it recognizes the device.
How to turn the camera on manually.
Maybe I wish to take a photo of something and save the image as a file.
The latest failure was trying to get photo of myself for travel via Airbnb. Their program gave a window to allow the camera but it never came on. Microsoft LifeCam HD 3000.