This won’t be of interest to very many of you (or: any of you), but I wanted to put this info on the web for others who will eventually be looking for it via Google, so ignore it if it doesn’t apply, and get lost!
Logitech has not provided, and I assume, will not be providing Windows 7 drivers for the oldish QuickCam Pro 4000 (which is still a perfectly fine piece of hardware, so why should I have to buy another one?)
It doesn’t matter. Do this: download the most recent Vista software, and run it. In the final step, the camera will fail to show an image, but ignore that. The software should be installed just fine, the only thing you’ll be missing is the driver.
Some people have had success getting that driver working by simply going through the normal install process, and then unplugging their camera and moving it to another USB port. Windows then detects the device and locates the driver on its own. But in case this doesn’t work for you (it didn’t work for me):
Go into your Control Panel, open “Hardware and Sound”, and then select “Device Manager” under “Devices and Printers” (or just “Device Manager”, if your Control Panel shows all items). You will see an “unknown device” marked by a yellow warning symbol. Double-click on that sucker, then select “Update driver”, choose “Browse my computer for driver software”, and navigate to (or cut and paste) the folder C:\Program Files\Logitech\QuickCamWebInstall\Drivers — make sure the “Include subfolders” box is checked. Hit “Next”, and Windows should install your device. This probably works for other webcam models as well.
You’re welcome. And Logitech, you’re lazy jerks!