I deleted a custom entity and its associated SDK message processing steps (create/update) by unregistering the step via plugin registration tool. I made these changes in my dev environment and then exported as managed solution to update the existing managed solution in my target environment. The import failed due to the plugin assemblies. I then unregistered the same steps from the target environment using the plugin registration tool, thinking this might help the managed import but the import still failed.
Both solutions have the same sdk message processing steps. No other changes were made to the plugin assemblies other than unregistering the same steps in both environments. Any ideas on why I'm encountering this failure and how I can fix it?