Hi @C1R,
If the method checks if attachments exist in the Email couldn't work, you could determine it directly as below:

Also, if does anyone know there is a way to include the following in the flow;
- Email numbered list should be converted into Task Checklist,
- The task priority should match the email importance
- Default setting should be the task 'Show on Card' enabled
Answer:
1. You could add the Email number into an Excel file instead of task checklist;
2. Set task priority is not supported currently, you could set the corresponding category according to the importance:
3. Set 'Show on Card' enabled is not supported.
Best Regards,
Community Support Team _ Lin Tu
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