Digital signature becomes invalid in Excel

Hello,

I’m having a problem with digitally signing an Excel file.
I want to exporting data from a grid to Excel. If I include a column containing rich text and a link, the signature becomes invalid upon opening the file. When the column is not included, the signature stays valid.

The steps I’m taking to generate a file are:

  • create a new workbook
  • fill it with data from my grid
  • build a DigitalSignatureCollection
  • Add the collection with workbook.AddDigitalSignature(digitalSignatureCollection);
  • save the workbook with workbook with workbook.Save(fileName);

One thing I noticed:
When I generate the file via aspose.cells, under Additional Information Signaturedetails I see Office- and Excel-Version to be 12.0. When I add a signature directly in Excel, Office- and Excel-Version are 16.0.

@HJW,

Thanks for providing us details.

Thanks for the sample code and error trace.

We need to evaluate your scenario/case a bit. Could you separate the issue and create a simple console (runnable) application (zip the project prior attaching) to reproduce the issue. Also, provide your certificate file and your template file and other resources (if any), so we could check your issue soon. Moreover, share some screenshots to highlight the error regarding signatures when opening the file. This will help us really to evaluate your issue precisely to consequently figure it out soon.