WebCam is in use by another application

1st You download Webcam Driver.
Logitech QuickCam driver After this install the Webcam driver in the system.
Installation of Webcam Driver
Go to the control panel
Click on the System Icon
Click on the Hardware Tab
Click on the Device Manager s
Select the Unknown Device or printer device where yellow Question Marks sign on it.
Right click on it and uninstall it.
After this go to the top of the device manager and click on scan for hardware changes.
Driver installation Wizard start.
Brows Your Driver from the Hard Disk and click on next.
Driver will be install.
Logitech Camera Drivers for Windows XP Vista Windows 7

Copy this site and paste it in your browser address bar and hit ENTER.

http://download.cnet.com/ManyCam-Virtual-Webcam/3000-2348_4-10593500.html?tag=mncol

to your web browser and paste it in the Address Bar and hit ENTER.
Then download the program and install it to start having fun with your camera and friends.

Manycam allows you to use your Webcam with multiple programs at the same time. Broadcast your
Webcam on MSN Messenger, Yahoo!, Skype, AIM, Paltalk, and Camfrog all simultaneously. Manycam
also allows you to add cool live CGI (computer generated special effects and graphics) to your
Webcam. Make it appear as if your face or hand is on fire with our "fire" effect.
Pretend you are underwater or make it look like it's snowing inside your house with the
Manycam underwater and snow effects. Add text, graphics, or your country's flag to your video
window.

ManyCam is the freeware tool for you if you use both CamFrog and ICQ, or any other video chat
program, and you want to use them simultaneously. It creates a "virtual" Webcam that
replicates your currently installed camera. It then lets multiple applications
access the video stream without conflict.

ManyCam is compatible with Yahoo, MSN, CamFrog, PalTalk, ICQ, Skype, YouTube, and more. Once
you've installed ManyCam, you need to set ManyCam as the primary input for program that you
want to use. ManyCam will automatically start when you activate your Webcam through that
program. The application includes a bunch of gimmicky features that let you change aspects of
the background and foreground. You can map a new pair of cartoon eyes over your face, and they
track pretty well to your movements, or you can show that your life is hell by replacing the
background with flames.

NOTE: There is an unfortunate toolbar that will install unless you opt out during setup, but
other than that ManyCam is worthy of a Webcam Oscar for cool and useful tech.

Hope this is of some help. Bud