How to Handle Encrypted Supplier PDF Decryption Failures in Invoice Pipelines

When a supplier's encrypted PDF fails to open due to a wrong password error, the recommended approach is to quarantine the file, preserve its original bytes with a cryptographic digest, and request correct credentials through an approved channel rather than retrying the same password. A wrong password error does not necessarily confirm the supplier provided incorrect credentials — the file may be truncated, altered in transit, or use encryption settings unsupported by the reader. In invoice processing pipelines, the failed attachment should be treated as a separate issue from invoice generation, which can proceed with an 'attachment-pending' state if policy allows. To prevent one bad attachment from consuming disproportionate worker resources, teams should maintain a dedicated queue for attachment inspection and monitor the age of held orders against delivery SLOs. Access to encrypted supplier files should be restricted to inspection workers, and sensitive data such as passwords or invoice contents must never be logged.