CKEditor disappears after I save my content

Hi. I am using Drupal 7 and the latest version of CKEditor. I just set up a new Drupal instance and I have been adding new content. Everything works as expected--CKEditor loads the correct profile for the text format I have set up.

But whenever I go back in to edit a piece of content I have already created, CKEditor does not display. It disappears from the top of the body field and all of the tags I entered previously appear unformatted.

I've tried everything I can think of to nail down what the issue is (and looked through the official bugs) to no avail. Has anyone seen this issue before? Thanks in advance.