CiviCase 'All cases' dashlet does not display any cases

I have about 28 cases in CiviCRM. I added the All Cases dashlet to my dashboard. At first, it displayed all of the cases, but after a few days, it only shows an error that reads "There are no Cases. Use Find Cases to expand your search." I have tried many times to refresh the dashboard, and have restarted my computer about a dozen times since this problem started. I can't figure out what I would have changed to make this dashlet break. Is it working for others? I have one colleague that it works for, and one for which it is broken, like mine. Ideas on how to fix it?