Can not delete assignments when original plugin not present

When clicking on the 'X' to delete a course, it does not delete the course. From Administration ? Courses ? Add/edit courses, I click on the 'X' next to the course I would like to delete. I am prompted with an 'are you sure?' question and select 'yes.' From there, it forwards to a page where it says 'deleting,' but that's it – it doesn't go anywhere from there and the course never deletes (see attachment). I know I have deleted courses from previous versions, so perhaps there was a bug introduced while fixing another? I am currently running 1.8+ (2007021503).