When loading a PDF generated with PdfProcessing in PDF Accessibility Checker 2021 (PAC) an exception is thrown: "Object reference not set to an instance of an object".
It is reproducible with all PdfComplianceLevel export options.
when parsing a specific document.
InvalidCastException caused by colorspace defined as nested indirect objects.
Unable to cast object of type 'Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.Model.Types.IndirectReference' to type 'Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.Model.Types.PdfName'.
Importing a document containing an EI keyword not followed by space or return leads to an endless loop and the document is not imported successfully.
Expected:
Actual:
Some documents loaded through WordsProcessing and then exported to a RadFixedDocument by utilizing the ExportToFixedDocument() method, fails on export through ImageFormatProvider with System.AggregateException.
As a workaround, you can export the RadFixedDocument to a PDF and then import it again before exporting it to an image.
var pdfFixedProvider = new Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.PdfFormatProvider();
bytes = pdfFixedProvider.Export(fixedDocument);
fixedDocument = pdfFixedProvider.Import(bytes);
When exporting documents containing TrueType Postscript fonts perceived as Standard fonts the fonts should not be embedded but they actually are.
Examples of such fonts are Arial MT, TimesNewRomanPSMT, etc.
When importing specific documents and signing a predefined SignatureField leads to not successfully validated signatures in Adobe, but successfully validated in other pdf viewers (eg. Telerik WPF PdfViewer, Foxit PDF Reader).
Solution:
When signing an existing document (after the import) we must be sure the AcroForm's ViewersShouldRecalculateWidgetAppearances property is set to false, otherwise, the exported and signed PDF document could not be shown as a signed.
if (document.AcroForm.ViewersShouldRecalculateWidgetAppearances)
{
document.AcroForm.ViewersShouldRecalculateWidgetAppearances = false;
}