Vista - built-in webcam issue

Hello. I have a Toshiba Satellite laptop (a355-s6925 with Vista home premium x64) that I purchased new a few months ago. The webcam (Chicony usb 2.0) worked fine until recently. I have a Camera Assistant software thing that I normally use. Previously, when I'd start it up, the little green light beside the camera would come on. Now it doesn't. It shows only a black screen instead of me. I tried disabling and enabling in the device manager. I tried updating drivers. I tried completely uninstalling the drivers and reinstalling. I tried a system restore to a date prior to the last time I used it...... Nothing is working!
On the Toshiba help site, there's an issue about the camera not working after it's returned from sleep mode. It linked to a windows hotfix which I downloaded. But the hotfix was for SONY computers. It did say on the hotfix site that it has been known to work with other computers, so I tried it. When I started it up, I got a message saying "This update does not apply to your system". Gotta love Microsoft.....

If anyone has any ideas short of calling the service number, I'd be thrilled to hear them. Thanks so much!

I Had a similar problem with my Toshiba Satellite. I just disabled my antivirus software and then tried it and it worked.