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. You can also use Invoice Navigator's automatic Fixer tool to correct this instantly.
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.
Many instances of KSEF-010 can be automatically corrected using Invoice Navigator's Fixer tool. Upload your invoice and the tool will identify and fix common issues, including ksef xml schema validation failed.
Last updated: 19 January 2026
Handle KSEF-010 Automatically in Your Pipeline
The compliance engine auto-remediates this error with controlled safety policies and evidence pack generation.