If you don't care about having controls for a PTZ and just want to view the live video stream, consider VLC. I've had it play a stream for over 24 hours without a hiccup.
You could create a desktop shortcut, modify the shortcut's "properties" to change the path to the cam's RTSP stream URL, including username and password as in the example below (sub your correct path to the VLC.exe, cam user/pass and IP, cam's RTSP URL of course). Also, place 2 "/" after "rtsp:", as forum software won't allow me to post 2 in a row.