NFE-924
Rejeição: Proibido referenciar Cupom Fiscal (refECF, a partir de …).
In English From 5 October 2026 (1 September in homologação) an NF-e may not reference a fiscal coupon (refECF).
What the rule checks
As the rule set's publisher wrote it. The rule runs on every element the context matches, and fails where the test is false; the validator reports the line of that element.
nfe:infNFe
not($paperBanned and $refs/nfe:refECF)
Checked with NF-e 4.00, NF-e 4.00 with authorisation protocol