We are working hard to bring you an end-to-end Stream Analytics experience in the new Azure portal and we are almost there! Now you can perform more troubleshooting tasks on portal.azure.com.
Input and output diagnosis: A yellow triangle warning sign on your input or output indicates something is wrong. Clicking on the warning sign will open the input/output property view and you can check out the error message.
You may also want to go to the job "Settings" "Audit logs" to see more detailed logs.
Still having no clue? Click on "New support request" in the Setting blade and open a support ticket. Azure support team will contact you shortly and help out.
You probably noticed the new "Error policy" setting we added recently. Now you can configure how your job handles output errors: drop the output data if write to destination fails, or retry until succeed. The default behavior is retrying on output errors, but if your scenario is safe to ignore some malformed events then "drop" option will increase robustness of your stream processing pipeline.
By the way, going forward new features like Error Policy will be available only on the new Azure Portal. It's time to get familiar with ASA's new portal experience!