errorubl-2.1

XML-004:Invalid XML characters

Document contains invalid XML characters.

Fix this in your source system

MANUAL

The document contains characters that are invalid in XML (control characters, incorrectly encoded bytes, etc.). This is typically caused by encoding mismatches or copy-paste from non-standard sources. Fix the source data in your ERP/invoicing system to use valid UTF-8 characters.

See the step-by-step instructions below to fix this error manually.

Why This Error Matters

Invalid characters break XML parsing.

How to Fix It

1

Find invalid chars

Control characters, invalid Unicode

2

Remove or escape

Use XML entities for special chars

Technical Details

Character validation

Common Causes

  • Control characters
  • Null bytes
  • Invalid Unicode

Frequently Asked Questions

Document contains invalid XML characters.
Remove or encode invalid characters. Invoice Navigator can help identify and fix this issue.
Yes, XML-004 is a critical error that must be fixed.

Related Errors

XML-002

Malformed XML structure

Last updated: 19 January 2026

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