Hi dear support,
We generate a pdf with Aspose version 17.3 and when this document is signed Acrobat reader refuse the signature with error message : “document has been altered or corrupted since it was signed”
Hotline of editor than provided electronic sign had analyzed the problem and discover than pdf-a generated do not respect section 7.5.4 of PDF norm :
“The table comprises one or more cross-reference sections. Initially, the entire table consists of a single section (or two sections if the file is linearized; see Annex F). One additional section shall be added each time the file is incrementally updated (see 7.5.6, “Incremental Updates”).
Each cross-reference section shall begin with a line containing the keyword xref. Following this line shall be one or more cross-reference subsections, which may appear in any order. For a file that has never been incrementally updated, the cross-reference section shall contain only one subsection, whose object numbering begins at 0.”
we have test it on simple pdf document with code line:
Aspose.Pdf.Document doc = new Aspose.Pdf.Document(inputPdfPath);
doc.Convert(new MemoryStream(), Aspose.Pdf.PdfFormat.PDF_A_2B, Aspose.Pdf.ConvertErrorAction.Delete);
I add documents on post :
- PDF.pdf : simple PDF
- PDF converted in PDFA_2B by ASPOSE.pdf
- PDF converted in PDFA_2B by ASPOSE and signed KO.pdf : you can open it with acrobat reader and find error
- PDFA generated by Word.pdf
- PDFA generated by Word and signed OK.pdf
This is a big problem for us because main aim of our application is to sign document and this signature is not valid ! I hope you can solve it with high priority.
PDF-A not valid.zip (622.5 KB)