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Version: 1.x

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

Server Error Mapping​

This error code is triggered when the server returns:

Server CodeSource
HTTP 400Any server response (fallback)

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