Webcam Help

[Desideratum]

So, I own a Windows 8 HP Envy dv6 Notebook PC (I think?). Honestly, I don't know much about computers so that may not be the correct information. However, today when I was Skyping my boyfriend, my video decided to stop working. A message popped up that read something about not being able to read or recognize the USB I had tried to plug in. At the time, nothing was plugged into the USB port. I restarted my laptop and Skype a few times, and it worked after a while only to go out an hour or so later. I've tried everything I can think of (which isn't much, admittedly) and don't know what to do. Help would be appreciated!

[Levente99]

A message popped up that read something about not being able to read or recognize the USB I had tried to plug in. At the time, nothing was plugged into the USB port.

This is confusing, was there or was there not a device plugged into a USB port?

[Allan]

She said there was nothing plugged in.

[soybean]

A point of clarification seems needed here.  Were you using the built-in webcam or a USB webcam, which means a device you plug in to a USB port?   And, if you have a built-in webcam, which is almost universal nowadays, why do you have a USB webcam?