Came upon this site via Gizmo's Freeware. Thought I would give it a try. As much as I can remember, this is a pretty complete description of the problem and all the steps I've taken to find a solution.
I have two Logitech webcams. The older one is the Quick Cam Communicate Deluxe. The newest is the c920 HD Pro. The Quick Cam one worked fine on XP Pro SP3.
I upgraded to Win7 Pro x64. I tried the Quick Cam and it would not show a picture. I contacted Logitech and after two visits, the second support person said the camera is broken and I needed to replace it. I was a little dubious but I've had it for awhile and so I purchased c920 hoping that this would resolve the problem.
I have been in touch with Skype and Logitech, have followed all of their instructions, and everything about both companies' programs works except for not being able to see a picture on the screen. I can, however bring up some old pictures saved to my computer from past use with the Quick Cam on XP.
Skype did give me a message that something else was using the camera. The responder from Skype sent information about a diagnostic which was supposed to show me what it was. The diagnostic said there wasn't another application using the camera. When I returned that answer, that was the last I heard from them.
I did try the c920 on my wife's computer and it works perfectly. I also tried a different USB port and that didn't help either.
The person who builds all my computers and repairs computers in addition to selling them, gave it a try and was unable to resolve it and he's pretty good. This is everything I can remember about what has happened concerning this problem.
Anyone have an idea?