10xxx · Message header
CESOP error 10010
“MessageRefID is not unique”
Only CESOP can raise it
What it means
The MessageRefId has been used by a message CESOP already holds. Every message is identified by it, so a second one with the same reference is refused.
Why files get it
- A rejected file resubmitted without generating a new MessageRefId.
- An exporter that derives the reference from something that repeats — the period, the PSP — instead of generating one.
- A test submission and the live one sharing a reference.
How to fix it
- Give every message a newly generated MessageRefId, including the resubmission of a message that was rejected.
- Generate a fresh UUID version 4 — for example 3f1a2b4c-5d6e-4f70-8a9b-0c1d2e3f4a5b — rather than composing the value from dates, names or counters.
Catch the rest before you file
10010 depends on data CESOP already holds, so no validator can raise it in advance. Most of the catalogue does not: the free validator checks a file against every rule that can be tested before submission and names the CESOP error each finding would become.
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Source: the error catalogue in the Payment Data XSD User Guide — CESOP, v4.40 (DG TAXUD), §2.2.3.18. The explanation is ours; it describes the file format and is not tax advice.