errorPEPPOL_BIS
PEPPOL-EN16931-CL001:Mime code must be according to subset of IANA code list.
The MIME type code for attachments must be from the IANA approved subset. Only specific file types are allowed for invoice attachments in PEPPOL.
We can fix this automatically
AUTO-FIXAuto-fix: Normalize MIME type to PEPPOL allowed values. Map common types to their standard codes, fix case. Safe code normalization.
No manual changes needed
Upload and Fix NowWhy This Error Matters
Invoice will be rejected by PEPPOL validation. Attachments must use approved MIME types for security and compatibility.
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
Frequently Asked Questions
The MIME type code for attachments must be from the IANA approved subset. Only specific file types are allowed for invoice attachments in PEPPOL.
The MIME type code for attachments must be from the IANA approved subset. Only specific file types are allowed for invoice attachments in PEPPOL. You can also use Invoice Navigator's automatic Fixer tool to correct this instantly.
Yes, PEPPOL-EN16931-CL001 is a critical error that will cause invoice rejection. It must be fixed before submission to ensure your invoice is accepted.
Many instances of PEPPOL-EN16931-CL001 can be automatically corrected using Invoice Navigator's Fixer tool. Upload your invoice and the tool will identify and fix common issues.
Last updated: 16 January 2026
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