It’s a common scene: You click "Run," the bot starts working, and suddenly—Stop. A red error message pops up, and your automation comes to a halt.
For a beginner, this is frustrating. For an intermediate developer, this is a diagnostic clue. In this guide, we will learn how to read these clues like a detective to locate, diagnose, and fix "Hard Errors" (errors that stop the flow).
The Universal 3-Step Debugging Framework
When a flow crashes, don't guess. Follow this logical framework:
Step 1: Read the Message. The error popup is your primary clue. Look for the Error Type (e.g., "Element Not Found") and the Target (e.g., the specific variable or button name).
Step 2: Locate the Instruction. Find the specific block in your editor that failed. Usually, Octoparse AI will highlight the instruction that caused the crash.
Step 3: Inspect & Fix. Check the parameters, selectors, or file paths of that instruction. Ask yourself: "Does this object exist at this exact moment?"
Common Scenarios & Troubleshooting Checklists
Most errors fall into four categories. Use these checklists to speed up your investigation:
Scenario A: Syntax & Data Type Errors
Symptoms: Type Mismatch or Invalid Expression.
Checklist: Are you trying to add a "Number" to a "String"? (e.g., 10 + "Apples"). Ensure variables used in calculations are of the correct type.
Scenario B: Object Reference Errors
Symptoms: Variable is not defined or File not found.
Checklist: Check for typos in your variable names. If it's a file error, ensure the folder path exists and the bot has permission to access it.
Scenario C: Web Element Failures (The Most Frequent!)
Symptom: Element Not Found
The Fix: Did the website change? Re-capture the element.
The Fix: Is the page too slow? Add a Wait command before the action to ensure the element has time to load.
Symptom: Multiple Elements Found
The Fix: Your selector is too vague. Refine your XPath or location strategy to make it unique so the bot doesn't get "confused" between two similar buttons.
Scenario D: Software Interaction Failures
Symptom: Cannot Activate Excel
Checklist: Is Office or WPS installed? Is the Excel file already open and "locked" by another program? Try closing Excel manually before running the bot.
Summary: The Mindset of a Fixer
When the flow stops, stay calm. Remember: Read → Locate → Inspect.
High-Frequency Error | Primary Solution |
Element Not Found | Check loading time (Wait) or re-capture element. |
Type Mismatch | Verify if the variable is a Number, List, or any others. |
File Not Found | Confirm the file path and permissions. |
Coming Up Next: What if the flow doesn't stop, but the data is completely wrong? We’ll dive into the world of "Silent Failures" and learn how to use advanced debugging tools.