errorubl-2.1

UBL-CR-002:Invalid or Missing Namespace

The UBL invoice must use the correct XML namespaces for UBL 2.1.

We can fix this automatically

AUTO-FIX

Auto-fix: Remove the disallowed element from the invoice XML. No data loss occurs because EN16931 explicitly prohibits this element.

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Why This Error Matters

Invoice will be rejected by PEPPOL/EN16931 validators. Safe to remove - this element is explicitly prohibited and contains no required business data.

How to Fix It

1

Add main namespace

xmlns="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2"

2

Add CBC namespace

xmlns:cbc="urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2"

3

Add CAC namespace

xmlns:cac="urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2"

Code Example

<Invoice xmlns="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2"\n         xmlns:cac="urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2"\n         xmlns:cbc="urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2">

Technical Details

XPath: /Invoice namespace declaration

Common Causes

  • Source ERP exports full UBL 2.1 instead of EN16931 subset
  • Generic UBL template includes optional elements not needed for e-invoicing
  • Conversion from another format added unsupported elements
  • Manual XML editing introduced non-standard elements
  • Invoice software not configured for EN16931 compliance

Commonly Seen In

Custom XML generatorsTemplate errors

Frequently Asked Questions

The UBL invoice must use the correct XML namespaces for UBL 2.1.
Add the correct UBL 2.1 namespace declarations to your invoice root element. You can also use Invoice Navigator's automatic Fixer tool to correct this instantly.
Yes, UBL-CR-002 is a critical error that will cause invoice rejection. It must be fixed before submission to ensure your invoice is accepted by the recipient's system.
Many instances of UBL-CR-002 can be automatically corrected using Invoice Navigator's Fixer tool. Upload your invoice and the tool will identify and fix common issues, including invalid or missing namespace.
UBL-CR-002 is commonly seen in exports from Custom XML generators, Template errors. These software packages sometimes generate invoices that need adjustment to meet full compliance standards.

Related Errors

UBL-CR-001

Invalid XML Syntax

Last updated: 16 January 2026

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