title: iPython Notebook/Jupyter autosave failed
body: <p>I am working in iPython 3/Jupyter running multiple kernels and servers. As such, i often forget to personally save things as I jump around a lot. The autosave has failed for the past 3 hours.
   The error says: "Last Checkpoint: 3 hours ago Autosave Failed! 
  I try to manually File>>Save and Checkpoint, and nothing changes. Help! 
  Next to my Python 2 kernel name, there is a yellow box that say forbidden instead of edit. It goes away when i click on it. I don't know if that has anything to do with the failure to save, but it doesn't change once clicked.</p>