errorbusinessPeppol BIS 3.0

`PEPPOL-EN16931-CL001`:Mime code must be according to subset of IANA code list.

Fix: Invoice Navigator automatically fixes this Invoice compliance issue by updating the relevant XML elements (PEPPOL-EN16931-CL001). Upload your invoice to fix this automatically.

Mime code must be according to subset of IANA code list.. This validation rule ensures Invoice compliance with Peppol BIS 3.0.

Severity

Fatal

Rule set

Peppol BIS 3.0

Country

All EU

Fix type

AUTO-FIX

Confidence

80%

Engine Classification

Suggest changing the MIME code to application/pdf (most common). User should confirm the attachment is actually a PDF.

Confidence: 80% · Applied automatically in pipeline

What is PEPPOL-EN16931-CL001?

PEPPOL-EN16931-CL001 is a fatal validation rule defined in the Peppol BIS 3.0 specification. It validates the @mimeCode element under Attachment > EmbeddedDocumentBinaryObject in the UBL invoice XML.

When this rule fires, the invoice is rejected by Peppol access points and never reaches the buyer.

Target path: //cac:AdditionalDocumentReference/cac:Attachment/cbc:EmbeddedDocumentBinaryObject/@mimeCode

Fix this error

Why This Error Matters

Invoice will be rejected by PEPPOL validation. Attachments must use approved MIME types for security and compatibility.

PEPPOL-EN16931-CL001 is a hard failure — the invoice must be corrected and re-sent before it can reach the recipient.

Peppol access points reject invoices with attachment MIME types outside the allowed list. Your attachment will not be delivered to the buyer until the file type is corrected.

Invoice Navigator can automatically correct this error in your pipeline. The fix is applied with full audit evidence, so your compliance trail remains intact.

Validator Behavior

·Causes invoice rejection
·Rejected by PEPPOL Access Points
·Error returned: PEPPOL-EN16931-CL001
·Specification: Peppol BIS 3.0

How to Fix It

Before / After

Failing XML

<Invoice>
  <!-- Issue: Mime code must be according to subset of IANA code list. -->
</Invoice>

Corrected XML

<Invoice>
  <!-- Issue resolved per Peppol BIS 3.0 -->
</Invoice>

Technical Reference

XPath//cac:AdditionalDocumentReference/cac:Attachment/cbc:EmbeddedDocumentBinaryObject/@mimeCode

SpecPeppol BIS 3.0

Operationset_value

StrategySuggest changing the MIME code to application/pdf (most common). User should confirm the attachment is actually a PDF.

Common Causes

·Unsupported MIME type used for attachment
·Typo in MIME type string
·Using full MIME type instead of abbreviated form
·Attachment type not in PEPPOL allowed list
·Case sensitivity issue in MIME type

Seeing this in production? The API handles PEPPOL-EN16931-CL001 automatically. See the fix response →

Frequently Asked Questions

Mime code must be according to subset of IANA code list.. This validation rule ensures Invoice compliance with Peppol BIS 3.0.

Invoice Navigator automatically fixes this Invoice compliance issue by updating the relevant XML elements (PEPPOL-EN16931-CL001). You can also use Invoice Navigator's compliance engine to correct this automatically in your pipeline.

Yes, PEPPOL-EN16931-CL001 is a critical error that will cause invoice rejection. It must be fixed before submission.

Many instances of PEPPOL-EN16931-CL001 can be automatically corrected using Invoice Navigator's compliance engine. The fix is applied in your pipeline with full audit evidence.

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PEPPOL-EN16931-CL001:Mime code must be according to subset of IANA code list.