Signing PDFs in parallel.

I get 

  at Syncfusion.Pdf.Security.Asn1Sequence.get_Item(Int32 index)

  at Syncfusion.Pdf.Security.PdfCmsSigner.Sign(Byte[] secondDigest, TimeStampServer server, Byte[] timeStampResponse, Byte[] ocsp, ICollection`1 crls, CryptographicStandard sigtype, String hashAlgorithm)

  at Syncfusion.Pdf.Security.PdfSignatureDictionary.GetPortableStoreCertificate()

  at Syncfusion.Pdf.Security.PdfSignatureDictionary.DocumentSaved(Object sender, DocumentSavedEventArgs e)

  at Syncfusion.Pdf.PdfDocumentBase.OnDocumentSaved(DocumentSavedEventArgs args)

  at Syncfusion.Pdf.Parsing.PdfLoadedDocument.Save(Stream stream)

when signing in parallel. In serial, one document after another, it works fine.



1 Reply

JT Jeyalakshmi Thangamarippandian Syncfusion Team March 18, 2026 12:56 PM UTC

Hi Ivan,

We have attempted to reproduce the reported issue; however, we were unable to replicate the problem on our end. 

To assist you further, we kindly request that you share the full code snippet or modified code snippet along with the PFX file with us. This will enable us to replicate the issue accurately and provide a more effective and timely solution

 

Please try the attached sample on your end and let us know if you need any additional assistance.



Regards,

Jeyalakshmi T


Attachment: ConsoleSample_36f63633.zip

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