title: Jupyter notebook - OSError [Errno 2] No such file or directory
body: <p>I had to install Jupyter in order to complete Udacity's projects. After following the instructions, and running Jupyter, none of the notebooks would open. This is the log output: </p>
  
  <pre><code>[W 06:54:04.215 NotebookApp] The signatures database cannot be opened; maybe it is corrupted or encrypted. You may need to rerun your notebooks to ensure that they are trusted to run Javascript. The old signatures database has been renamed to /home/aulon/.local/share/jupyter/nbsignatures.db.bak and a new one has been created.
  [E 06:54:04.218 NotebookApp] Unhandled error in API request
      Traceback (most recent call last):
        File "/home/aulon/.local/lib/python2.7/site-packages/notebook/base/handlers.py", line 516, in wrapper
          result = yield gen.maybe_future(method(self, *args, **kwargs))
        File "/home/aulon/.local/lib/python2.7/site-packages/tornado/gen.py", line 1055, in run
          value = future.result()
        File "/home/aulon/.local/lib/python2.7/site-packages/tornado/concurrent.py", line 238, in result
          raise_exc_info(self._exc_info)
        File "/home/aulon/.local/lib/python2.7/site-packages/tornado/gen.py", line 307, in wrapper
          yielded = next(result)
        File "/home/aulon/.local/lib/python2.7/site-packages/notebook/services/contents/handlers.py", line 124, in get
          path=path, type=type, format=format, content=content,
        File "/home/aulon/.local/lib/python2.7/site-packages/notebook/services/contents/filemanager.py", line 384, in get
          model = self._notebook_model(path, content=content)
        File "/home/aulon/.local/lib/python2.7/site-packages/notebook/services/contents/filemanager.py", line 344, in _notebook_model
          self.mark_trusted_cells(nb, path)
        File "/home/aulon/.local/lib/python2.7/site-packages/notebook/services/contents/manager.py", line 456, in mark_trusted_cells
          trusted = self.notary.check_signature(nb)
        File "/home/aulon/.local/lib/python2.7/site-packages/traitlets/traitlets.py", line 556, in __get__
          return self.get(obj, cls)
        File "/home/aulon/.local/lib/python2.7/site-packages/traitlets/traitlets.py", line 535, in get
          value = self._validate(obj, dynamic_default())
        File "/home/aulon/.local/lib/python2.7/site-packages/notebook/services/contents/manager.py", line 58, in _notary_default
          return sign.NotebookNotary(parent=self)
        File "/home/aulon/.local/lib/python2.7/site-packages/nbformat/sign.py", line 390, in __init__
          self.store = self.store_factory()
        File "/home/aulon/.local/lib/python2.7/site-packages/nbformat/sign.py", line 338, in factory
          return SQLiteSignatureStore(self.db_file)
        File "/home/aulon/.local/lib/python2.7/site-packages/nbformat/sign.py", line 147, in __init__
          self.db = self._connect_db(db_file)
        File "/home/aulon/.local/lib/python2.7/site-packages/nbformat/sign.py", line 171, in _connect_db
          os.rename(db_file, old_db_location)
      OSError: [Errno 2] No such file or directory
  ...
  </code></pre>
  
  <p>I googled and found some similar problems <a href="https://github.com/jupyter/notebook/issues/1171" rel="nofollow noreferrer">here</a>, <a href="https://github.com/jupyter/notebook/issues/2301" rel="nofollow noreferrer">here</a>, and <a href="https://github.com/ipython/ipython/issues/9163" rel="nofollow noreferrer">here</a>, without success.</p>
  
  <p>I installed Anaconda, still the same problem. </p>
  
  <p>Any help is much appreciated. </p>
  
  <p>If I cannot solve this, how can I fully uninstall everything related to jupyter and anaconda? I am using Ubuntu 16.04. </p>
  
  <p>Otherwise, is there any other way I can open a python notebook without jupyter? Maybe Spyder?</p>