KSEF-010:KSeF XML schema validation failed
Invoice XML must conform exactly to the FA schema version (FA/1 or FA/2). Even minor deviations cause rejection.
Engine Classification
Financial or legal field · Modification blocked by policy
Reason: The invoice XML does not conform to the KSeF FA schema (FA/1 or FA/2). Schema validation failures indicate fundamental structural issues that cannot be automatically corrected. Your invoicing software must be updated to generate KSeF-compliant XML. Contact your software vendor for KSeF compliance updates.
What is KSEF-010?
KSEF-010 is a fatal validation rule defined in the KSeF specification (POL national rules). It checks whether ksef xml schema validation failed.
When this rule fires, the invoice is non-compliant and will be rejected by Peppol access points and national validation services. The sending system receives a rejection response and the invoice does not reach the buyer.
Why This Error Matters
KSEF-010 is a hard failure. Invoices that trigger this rule are rejected at the access point and never reach the recipient. In Peppol networks, this means your sending system receives an MLR (Message Level Response) with a rejection status. The invoice must be corrected and re-sent, adding delay to your payment cycle.
Validator Behavior
- ·Causes invoice rejection
- ·Error returned: KSEF-010
- ·Specification: KSeF
How to Fix It
Technical Reference
Common Causes
- ·Missing required elements
- ·Invalid element order
- ·Software not updated to latest schema
Seeing this in production? The API handles KSEF-010 automatically. See the fix response →
Frequently Asked Questions
Invoice XML must conform exactly to the FA schema version (FA/1 or FA/2). Even minor deviations cause rejection.
Validate XML against current FA schema before submission. This error involves a protected field — Invoice Navigator flags it in your pipeline so your team can correct it at the source.
Yes, KSEF-010 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.
KSEF-010 involves a financial or legal field that cannot be auto-modified by policy. Invoice Navigator detects and flags this error immediately, but the correction must be made manually in your ERP or invoicing software.
Related Content
Last updated: 3 March 2026
Detect KSEF-010 Before Submission
This error involves a financial or legal field that cannot be auto-modified. The compliance engine flags it immediately with a clear diagnosis so your team can fix it at the source.