API03001: Invalid Request Format
What This Means
The request sent to the server was not in the expected format. The server couldn't understand what the POS was asking for because the request structure was incorrect.
Common Causes
- Corrupted data — Data was corrupted before sending
- Software bug — An issue in the POS application
- Proxy interference — A proxy or firewall modified the request
- Character encoding issues — Special characters weren't encoded properly
How to Fix
1. Retry the Action
Sometimes this is a one-time glitch:
- Wait a moment and try again
- Refresh the POS and retry
2. Check for Special Characters
If you're entering data with special characters:
- Try removing emojis or unusual symbols
- Use standard characters for product names, etc.
3. Update the POS
Ensure you're running the latest version:
- Check for app updates
- Update the WCPOS plugin on your server
4. Check Network Configuration
If you're behind a proxy:
- Verify the proxy isn't modifying requests
- Check firewall rules
- Try accessing from a different network
5. Report the Issue
If this happens consistently:
- Note what action triggers the error
- Check browser console for details (web version)
- Report on GitHub with reproduction steps