Overview of error messages when submitting invoices by email, with causes and solutions.
When a submitted invoice cannot be processed, you receive an error message by email at the address from which you sent the invoice. Below is an overview of the most common error messages, with the cause and the solution for each message.
Delivery error messages
You receive these error messages immediately after sending the email, before the document is processed by the IDR. They concern the email itself or the file format.
MessageMeaningSolutionNo (valid) attachment(s) / "Processing is not possible"The email contains no attachments, the attachments are in an unsupported format, or an attachment is larger than 10 MB. Use PDF, XML, JPEG, JPG, PNG or BMP. Files smaller than 1 KB are ignored. A PDF that is too large can drop out as unprocessable without showing the explicit limit message.Check that you attached the invoice, that the file format is supported, and that the file is smaller than 10 MBToo many attachmentsThe email contains more than 50 attachments. This maximum is set to keep processing reliable.Split the invoices across multiple emails, each with a maximum of 50 attachmentsFile size exceeds limitAn individual file is larger than 10 MB, or the total email is larger than 35 MB.Reduce the file size (for example by compressing the PDF) or split the invoices across multiple emailsDocument protectedThe PDF is protected with encryption, a digital signature or other restrictions, so the text cannot be read.Remove the protection from the PDF, print the document to PDF again (for example with Microsoft Print to PDF) or ask the supplier to send an unprotected versionPDF form (interactive form fields)The PDF contains interactive form fields (AcroForm/XFA) instead of plain text, so the content cannot be read.Open the document and print it to PDF again (for example with Microsoft Print to PDF), then submit the new, flat PDFError occurred during processingA technical error occurred. The document is automatically offered again within 24 hours (on business days).Wait. If the document has not been processed after 24 hours, contact support
Processing error messages (conversion)
You receive the messages below after the document has been submitted and the IDR has tried to process it. They concern the content or the type of the document.
MessageMeaningSolutionEssential elements missingEssential data cannot be determined (for example invoice number, date, amount or other required fields)Check that the invoice is completeDocument type is incorrectNot an invoice or order (for example quotation, packing slip, terms and conditions)Submit only invoices; send other documents as an attachmentReminder or payment requestDocument recognised as a reminderSubmit the original invoiceDocument unreadableDocument is not readable (for example resolution too low, poor lighting, damaged file or blank page)Check the source file and submit a readable versionDocument contains multiple documentsMore than one invoice in one PDFSplit into one invoice per fileDocument recognised as logoImage from an email signatureUsually filtered correctly; if wrong: submit as PDFSelf-billing invoiceWrong receiver (purchase vs sales)Send to the correct email address
Tip: if error messages keep recurring, first check the requirements for submitting. Many problems can be prevented by using the correct file formats and limits.
Invoice number with spaces
An invoice number with spaces is not an error message and not a defect. During PDF conversion the system always removes all spaces from the invoice number. That is product normalisation. Supplier XML (Peppol or an XML upload) keeps the invoice number as supplied, including spaces.
Duplicate detection compares exactly on supplier, invoice date and invoice number. Only a space difference between the PDF conversion and the supplier XML produces two originals, not a duplicate and not an incident. If the PDF conversion differs from the XML, submit only the XML. You correct a different file name at the sender.
Frequently asked questions
Where do I receive error messages if my invoice cannot be processed?
Error messages are sent by email to the address from which you submitted the invoice. Make sure this address is a working mailbox that someone reads. For a trusted sender you can set a separate contact email address for error messages.
What should I do with the error message "Document contains multiple documents"?
This message means that the PDF file contains more than one invoice. Split the file so that each invoice is in a separate PDF file and submit the files again. An invoice of several pages may stay in one PDF.
Is a failed invoice offered again automatically?
Only for the error message "Error occurred during processing" is the document automatically offered again within 24 hours on business days. For all other error messages you must resolve the problem yourself and submit the document again.