45xxx · Reported transaction
CESOP error 45050
“The 'TransactionIdentifier' element is not unique within the system”
Only CESOP can raise it
What it means
The TransactionIdentifier has already been reported in a message CESOP holds. It identifies one payment, so it cannot appear again as a new transaction.
Why files get it
- A quarter's file sent twice as new data.
- Payments from the previous quarter's tail included again.
How to fix it
- Report each payment once. To change a payee already on file, correct that payee (CESOP2) rather than resending its payments as new data.
Catch the rest before you file
45050 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.
The file is parsed in your browser tab. No upload, no account.
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.