Check the following:
Is your camera plugged in?
If you’re using an external webcam rather than a built-in one, make sure that it’s plugged in and switched on. If it’s connected to your computer by USB, try plugging it into a different USB slot. If you’re using a USB hub, try plugging the camera directly into a USB slot on your computer instead – and try disconnecting your other USB devices.
Is another application using your webcam?
Close any applications that might be using your webcam – including video-editing software, virtual camera software, instant messengers and internet browsers. If your webcam has a light to show when it’s in use and you see it when you’re not in a Skype call, then some other application is using your camera.
Is your webcam installed correctly?
Check that your camera is listed and enabled in Device Manager – even if you’re using the computer’s built-in camera. To get to Device Manager:
In Windows 10 and Windows 8 desktop: Tap the Windows key and type Device Manager. Choose it from the results.
In Windows 7: Click the Windows button and select Control Panel. Make sure that Category is selected in the top right corner, next to View by:. Click Hardware and Sound. Under Devices and Printers, select Device Manager.
In Windows Vista: Click Start > Control Panel. Open System and Maintenance and click Device Manager.
In Windows XP: Click Start > Control Panel. Open System and, in the Hardware tab, click Device Manager.
Under Imaging devices, check that your camera is listed.
If it is listed, make sure it’s enabled. Right-click and select Enable (if you see a Disable option, then the camera is already enabled).
If it’s not listed, or if it has a question mark or exclamation mark, you’ll need to reinstall the camera. You can find the latest drivers for your camera on the internet – try searching for the camera model on Bing.
Do you have the latest version of DirectX?
Make sure that you have the latest version of Microsoft DirectX. For Windows Vista and Windows 7, you can get the latest version of DirectX by updating Windows with the latest service packs and updates. For Windows XP, you can download it here.
After you’ve checked all of the above, sign out of Skype (click Skype > Sign out) and in the Welcome to Skype window, uncheck the option Sign me in when Skype starts.
Restart your computer, then sign in to Skype and check again that Skype can see your camera.