It's easy to go course-blind and sometimes your exercises aren't going to work. Knowing some common mistakes could save you loads of time debugging your course.
Follow these steps to debug:
Click on the Preview button to view your exercise on "Campus".
Let your exercise load. If you see the following message in the R console/Python shell, it is likely one of the common mistakes listed below. Click the "Close" button to get a printed error message for more information.
Common mistakes:
Forgetting to load a package in the pre-exercise code (PEC).
Accidentally adding scaffolding to the solution code.
Updating one part of your code (solution or sample), but not the other.
If your exercise loads, but the "Oops" message appears after submitting the exercise, there is likely something wrong with the Submission Correctness Test (SCT) block. Double check that the syntax of your success_message() is correct, comment out any other SCT-related code, and then try running your exercise in the preview again. If the exercise still doesn't run, you can contact your Curriculum Manager or Content Developer for assistance.