Handle the import of documents that have an invalid boolean value for the PrintScaling property of ViewerPreferences. The expected value of the /PrintScaling entry is a PDF name object:

When importing such documents, the following exception is thrown: 

 

 

Incorrect CID font resolution corrupts text after import-export.

Incorrect character spacing when importing CID fonts with the same BaseFont and different width tables.

Using the PdfStreamSigner to set signature Properties like Name, Location, Reason, and ContactInfo is not respected after export.

Importing the attached PDF throws InvalidCastException while parsing its structure tree. A /Layout attribute sets /BorderThickness to integer scalar 1. ISO 32000-1:2008 allows this value as a number or a four-entry array; a scalar applies to all four edges. The importer handles real values and arrays, but not PdfInt.

Setting PdfImportSettings.IgnoreMarkedContent to true currently skips marked-content containers but still imports the structure tree, so it does not avoid the exception.

Expected: Import integer and real scalar values as thickness for all four edges; preserve four-entry array values. When IgnoreMarkedContent is true, skip structure-tree import while still importing pages.

InvalidCastException is thrown when importing a PDF with a CR-terminated comment in its /Info dictionary.

Missing/corrupted font characters during multithreaded PDF export.

Currently, font registration APIs accept only byte[], requiring callers to load the entire font file into memory before passing it to the library. This can be problematic for large font files, especially CJK fonts, which can significantly increase application memory usage.

InvalidOperationException: 'isContentReleased' is thrown when appending pages with shared image content to a new document using the PdfStreamWriter.

PDF export fails after HTML blocks containing empty or named anchors are imported and inserted into a RadFlowDocument through ReplaceText.

HTML importer creates hyperlink field markers for <a name="...">. During block replacement, cloned FieldCharacter instances lose FieldInfo, leaving orphan field markers. PDF exporter later dereferences FieldInfo and throws a NullReferenceException.

Wrapped table cell text is incorrectly split by hyphens ("-").

This is a regression introduced in version 2026.3.826. Use an older version to avoid this issue.

When two PDFs containing AcroForm fields are merged with PdfStreamWriter, the generated PDF contains page widget annotations whose parent field dictionaries are not correctly registered in the document-level /AcroForm/Fields tree.

The issue is reproducible by merging the same four-page form twice. The resulting PDF contains all widget annotations, but PDF viewers do not resolve the second form’s interactive fields correctly.

Merging/importing PDFs with duplicate field names can create one logical RadioButtonField containing widgets from multiple source field nodes. The first node initializes its widget options. Reused duplicate nodes can add additional widgets without assigning RadioOption instances.

The widgets then contain valid "/Off" appearance states, but their model Option property is null. During export, FieldPropertiesExporter accesses widget.Option.Value, causing a "NullReferenceException: Object reference not set to an instance of an object."

Endless loop on PDF export when an empty string is assigned to text fields with no source /V and auto-sized default appearance (/DA with 0 Tf).

Workaround: Instead of an empty string (""), set the value to null. Or don't set it at all and leave it unmodified.

InvalidCastException is thrown when importing a document that contains structure elements (StructElem) with StructureType (/S) defined with an incorrect integer type (PdfInt) instead of the expected PdfName type.

When the text is long and AllowScroll is false, the text will be visible, but will be misplaced. The issue is caused by the length of the text because the same field with a shorter text that can fit in the widget's rectangle will be displayed correctly.

When signing a PDF document with an image using the PdfStreamSigner, the signature is broken. This is the used approach for signing the document: https://www.telerik.com/document-processing-libraries/documentation/libraries/radpdfprocessing/features/digital-signature/pdfstreamsigner

However, instead of using the DrawText method, the DrawImage method is used.

 

NotImplementedException is thrown for GetCapHeight method of CFFFontSource.

System.NotImplementedException: The method or operation is not implemented.
   at Telerik.Windows.Documents.Core.Fonts.Type1.CFFFormat.CFFFontSource.GetCapHeight()
   at Telerik.Windows.Documents.Core.Fonts.FontSource.get_CapHeight()
   at Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.Model.Elements.Fonts.FontDescriptor.CopyRequiredButType3FontPropertiesFrom(FontBase font)
   at Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.Model.Elements.Fonts.FontDescriptor.CopyPropertiesFrom(IPdfExportContext context, FontBase font)
   at Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.Model.Elements.Fonts.CidFontObject.CopyPropertiesFromOverride(IPdfExportContext context, FontBase font)
   at Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.Model.Elements.Fonts.Type0FontObject.CopyPropertiesFromOverride(IPdfExportContext context, FontBase font)
   at Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.Export.PdfExporter.WriteFontsFromContext(PdfWriter writer, IPdfExportContext context)
   at Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.Export.PdfExporter.Export(IRadFixedDocumentExportContext context, Stream output)
   at Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.ExceptionHandling.ExecutionHandler.TryHandleExecution[E](Action operation)
   at Telerik.Windows.Documents.Fixed.FormatProviders.Pdf.PdfFormatProvider.ExportOverride(RadFixedDocument document, Stream output, CancellationToken cancellationToken)
   at Telerik.Windows.Documents.Common.FormatProviders.FormatProviderBase`1.Export(T document, Stream output, Nullable`1 timeout)

Corrupted character spacing when exporting PDF/A compliance document with embedded subset fonts.

Glyphs Overlap Due to Incorrect Casting of Glyph Widths from Double to Int.