'Invalid protocol' error
Why do I get an "Invalid protocol" error message?
RealTimes and RealPlayer can open web addresses (URLs) that start with rtsp://, pnm://, or http://. If you try to connect to a different type of URL, you may get this error message:
Invalid protocol specified in URL. URLs should typically start with "rtsp://", "pnm://", or "http://"
If you received this error message, check if you typed the URL correctly--including the http://, pnm://, or rtsp:// prefix--and try it again. If you clicked on a link, go back to the source to verify the URL.