Steps to fix it video calling disabled on Skype:

• On Windows, Skype updates automatically, but you can force an update by uninstalling the programme and downloading the most recent version. To uninstall, go to Start and type skype. Expand the list in the shown result and click Uninstall Highlight Skype in the Programs and Features window and choose Uninstall from the drop-down menu.
• Make sure the webcam is turned on when you start a video chat with a friend. Skype video calling will be disabled if this does not happen. This can be resolved via the Device Manager. Simply locate the camera, enlarge it, right-click on the device name, and choose Enable Device from the menu. For this modification to take effect, your computer may need to be rebooted.

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