If your webcam is not detected at some point during the pre-exam webcam check, and you see the below message, it is likely caused by 3rd party anti-virus software that is installed on your computer. It's also possible that you aren't seeing the below message, but rather are experience a freeze/hang on one of the steps. This, too, may be caused by anti-virus software.
The most problematic of these are Avast, AVG and McAfee. The below suggestions are methods you can use to work around the problem. If you choose to implement either of the below workarounds, be sure to re-enable your McAfee anti-virus real time scanning, AVG Realtime Protection, or Avast File System Shield once the exam is finished.
If you have McAfee installed, you should first try to disable “Real-time Scan” in McAfee Total Protection. To do this, go to:
McAfee Total Protection Preferences->General->Real-time Scan and set it to "OFF" as shown in this screen print:
Afterwards, try to take your exam again. If the problem persists, you should temporarily disable McAfee.
If you have AVG for Mac installed, you can temporarily disable the "Realtime Protection" via the user interface. The screen print below shows Realtime Protection turned on. You need to click on this and set it to "off".
If you have Avast installed, first try disabling the “File System Shield” in Avast Preferences. (Avast->Preferences->File System Shield).
Afterwards, try your exam again. If the problem persists, try temporarily disabling Avast completely.