Digital Signature Issue

Question

There is an issue related to Digital Signature, when adding multiple signatures to a pdf with pdf version 1.3 that was exported from Microsoft Reporting Services SSRS 2017 and earlier ... the first signature becomes invalid with the below error
There are errors in the formatting or information contained in this signature (support information: SigDict /Contents illegal data

Attachment: prototype_e10aa13c.zip

Gowthamraj Kumar · Answer

Hi Mohamed, 
The earlier file version “1.3” or below does not support incremental updates and so we have always allowed the document to rewrite the entire file and it causes the first signature to become invalid when the second sign. However, we can overcome this issue by setting the file version to “1.4” or above and rewrite the entire file for an initial sign. 
 




            //Load PDF document  
            PdfLoadedDocument loadedDocument = new PdfLoadedDocument(file); 
 
            if ((loadedDocument.FileStructure.Version == PdfVersion.Version1_0 || loadedDocument.FileStructure.Version == PdfVersion.Version1_1 || loadedDocument.FileStructure.Version == PdfVersion.Version1_2 || loadedDocument.FileStructure.Version == PdfVersion.Version1_3)) 
            { 
                loadedDocument.FileStructure.Version = PdfVersion.Version1_4; or above 
                loadedDocument.FileStructure.IncrementalUpdate = false; 
            } 
 
 
Regards, 
Gowthamraj K