title: Celery + Django: Cannot start celerybeat on Windows 7
body: <p>I've been developing a Django application and I am now trying to add Celery for background tasks. I need both normal tasks and periodic tasks to be queued. I can start up celeryd just fine, and execute tasks with it (I start it with the command <code>python manage.py celeryd start --settings=settings --loglevel=INFO</code>).</p>
  <p>On Windows you can't do <code>-beat</code>/<code>-b</code> to enable beat mode; you need to start celerybeat as a separate service (this is stated in the FAQ section of the Celery docs). If I type this into the command line -- <code>python manage.py celerybeat -s djcelery.schedulers.DatabaseScheduler --settings=settings --loglevel=INFO</code> -- I get an error like this:</p>
  <pre><code>[2012-01-02 19:06:52,009: WARNING/MainProcess] ERROR: Pidfile (celerybeat.pid) a
  lready exists.
  Seems we're already running? (PID: 2364)
  [2012-01-02 19:06:52,012: INFO/MainProcess] process shutting down
  </code></pre>
  <p>and celerybeat never actually starts. So I can't execute any periodic tasks ... Any ideas? I only found <a href="https://stackoverflow.com/questions/4323300/django-celery-beat-crashes-on-start">one other page</a> where somebody highlighted a similar error, but no solution was offered.</p>
  <p>If there's any further information needed, please let me know. I'm baffled because I can't find any information on this subject, and I've been trying solve this problem all day today ... Thank you.</p>