title: Jupyter Notebook 404s when using Anaconda Navigator
body: <p>Sorry but a bit of a beginner question here. I downloaded Anaconda library that comes with Jupyter Notebook along with a few other programs to hopefully learn Python. Every time I try to open Jupyter Notebook though, the webpage it directs me here <code>localhost:8888/tree</code> and gives me the following error:</p>
  
  <blockquote>
    <p>404: Not Found error webpage.</p>
  </blockquote>
  
  <p><strong>Edit</strong>: After using the terminal to install pip, I got the following error message:</p>
  
  <pre><code>Exception:
  Traceback (most recent call last):
    File "C:\Users\Y510P\Documents\Anaconda\lib\shutil.py", line 387, in _rmtree_u
  nsafe
      os.unlink(fullname)
  PermissionError: [WinError 5] Access is denied: 'C:\\Users\\Y510P\\AppData\\Loca
  l\\Temp\\pip-0tanc911-uninstall\\users\\y510p\\documents\\anaconda\\lib\\site-pa
  ckages\\zmq\\backend\\cython\\constants.cp36-win_amd64.pyd'
  
  During handling of the above exception, another exception occurred:
  
  Traceback (most recent call last):
    File "C:\Users\Y510P\Documents\Anaconda\lib\site-packages\pip\basecommand.py",
   line 215, in main
      status = self.run(options, args)
    File "C:\Users\Y510P\Documents\Anaconda\lib\site-packages\pip\commands\install
  .py", line 342, in run
      prefix=options.prefix_path,
    File "C:\Users\Y510P\Documents\Anaconda\lib\site-packages\pip\req\req_set.py",
   line 795, in install
      requirement.commit_uninstall()
    File "C:\Users\Y510P\Documents\Anaconda\lib\site-packages\pip\req\req_install.
  py", line 767, in commit_uninstall
      self.uninstalled.commit()
    File "C:\Users\Y510P\Documents\Anaconda\lib\site-packages\pip\req\req_uninstal
  l.py", line 142, in commit
      rmtree(self.save_dir)
    File "C:\Users\Y510P\Documents\Anaconda\lib\site-packages\pip\_vendor\retrying
  .py", line 49, in wrapped_f
      return Retrying(*dargs, **dkw).call(f, *args, **kw)
    File "C:\Users\Y510P\Documents\Anaconda\lib\site-packages\pip\_vendor\retrying
  .py", line 212, in call
      raise attempt.get()
    File "C:\Users\Y510P\Documents\Anaconda\lib\site-packages\pip\_vendor\retrying
  .py", line 247, in get
      six.reraise(self.value[0], self.value[1], self.value[2])
    File "C:\Users\Y510P\Documents\Anaconda\lib\site-packages\six.py", line 693, i
  n reraise
      raise value
    File "C:\Users\Y510P\Documents\Anaconda\lib\site-packages\pip\_vendor\retrying
  .py", line 200, in call
      attempt = Attempt(fn(*args, **kwargs), attempt_number, False)
    File "C:\Users\Y510P\Documents\Anaconda\lib\site-packages\pip\utils\__init__.p
  y", line 102, in rmtree
      onerror=rmtree_errorhandler)
    File "C:\Users\Y510P\Documents\Anaconda\lib\shutil.py", line 494, in rmtree
      return _rmtree_unsafe(path, onerror)
    File "C:\Users\Y510P\Documents\Anaconda\lib\shutil.py", line 384, in _rmtree_u
  nsafe
      _rmtree_unsafe(fullname, onerror)
    File "C:\Users\Y510P\Documents\Anaconda\lib\shutil.py", line 384, in _rmtree_u
  nsafe
      _rmtree_unsafe(fullname, onerror)
    File "C:\Users\Y510P\Documents\Anaconda\lib\shutil.py", line 384, in _rmtree_u
  nsafe
      _rmtree_unsafe(fullname, onerror)
    [Previous line repeated 5 more times]
    File "C:\Users\Y510P\Documents\Anaconda\lib\shutil.py", line 389, in _rmtree_u
  nsafe
      onerror(os.unlink, fullname, sys.exc_info())
    File "C:\Users\Y510P\Documents\Anaconda\lib\site-packages\pip\utils\__init__.p
  y", line 114, in rmtree_errorhandler
      func(path)
  PermissionError: [WinError 5] Access is denied: 'C:\\Users\\Y510P\\AppData\\Loca
  l\\Temp\\pip-0tanc911-uninstall\\users\\y510p\\documents\\anaconda\\lib\\site-pa
  ckages\\zmq\\backend\\cython\\constants.cp36-win_amd64.pyd'
  </code></pre>