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Locate the Audio menu at the upper right of the Webex application.
Click Integrated Voice Conference > Join Conference.
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How to open your camera
Make sure that your camera is not being used by other programs such as Skype or Zoom
To open your camera you need to click to the icon camera next to your name as indicated below
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3. Your microphone will be opened by your lecturer that's why it is disable to you, but again you need to make sure that it is not being used by any other programs. You can also use headphones.