I'd look into Add A New Plottter and direct it towards the same plotter, but give it a different name. If it doesn't crash AutoCAD when you plot to it, then you've narrowed down the search to your old (current) plot configuration. If you've got any applications that use the old (current) plotter configuration that may cause a search and replace headache, just delete the old (current) one, and rename the new one (assuming it works) to the old name.
Just a shot in the dark.