If you encounter the 404: Not Found error
Click on the Control panel button and restart
The server starts fine but you if you are still unable to get latest code by Advanced-> Sample Application -> "click refresh and check for new updates."
Click connect and create -> Myfiles
Start a terminal session
rm -rf ~/Reference-samples/
rm -rf ~/.jupyter/.staging_complete
Click on "control panel" on the top right
STop my server and Start my Server
This should fix the problem
For more complete information about compiler optimizations, see our Optimization Notice.