A camera or microphone is missing

Cilevi lists what Windows tells it about. If a device is not in the list, Windows is not offering it, and the fix is usually outside Cilevi.

Check in this order

Is it plugged in and awake? A phone acting as a webcam usually has to be unlocked, with its app in the foreground.

Does it work anywhere else? Open the Windows camera app, or the sound settings, and see whether the device appears there. If it does not, the problem is the driver or the cable, not Cilevi.

Is another program holding it? Windows lets one program at a time have some cameras. A video call left open in a browser tab is the usual culprit, and closing the tab is not always enough: quit the program.

Is it blocked by privacy settings? Windows has a master switch for camera and microphone access per app. Check Settings, then Privacy and security.

Did you plug it in after opening Cilevi? Reopen the menu, which re-reads the list.

The cases where it never appears

A phone's microphone over a webcam connection. Most of those connections expose video only. Windows never sees a microphone, so Cilevi cannot list one. Use a separate microphone.

A virtual audio device that is not producing sound. Some virtual mixers appear in the list and then record silence because nothing is routed into them. That is a setting in the mixer.

The camera appears but shows nothing

Usually another program still has it. If not, unplug it and plug it back in, then reopen the camera menu.