Internal cameras on All in One computers may conflict with external USB cameras.
To resolve camera conflicts disable the internal camera via MS Windows Device Manager.
Right Click Start Menu (Lower left corner "Window-Panes")
Select "Device Manager" and locate the Internal Camera from the drop down list.
This should be located under "Cameras".
Select the > arrow to expand the list of devices.
Locate the correct camera and "Right Click" and then select "Disable Device"
Note:
USB cameras are normally listed under "Universal Serial Bus Controllers (USB)" however it is possible they are listed under the "Cameras" list.
If the external camera is no longer working after completing the "disable" steps, the wrong camera may have been disabled and the steps need to be repeated to "Enable" the camera and the correct "internal" camera is selected to disable.