PDF Annotation on signed PDF document

Hello,



I need to make annotation to signed PDF document. When I create a FreeTextAnnotattion and add it to the page, then I have invalid signature (Acrobat reader say SigDict/Contentes illegal data). I tried it also with latest version of aspose.pdf.dll (.net framework 2.0)



I attached the document with signature (before annotation - Doc_Signed.pdf) and after annotation - Doc_annotation.pdf



Regards



Pavel Vlcek

Hi Pavel,


Thanks for using our API’s.

The digital signature in PDF document ensures that no modifications / alterations are made in PDF document and in case some changes are made, the signature becomes invalid.
Hi Nayerr,

yes, you are right that signature is used for document integrity. But annotation is possible to add to the document (when I do it with Acrobat Reader for example), then I have signed document and later added annotation - like attachement. It must be possible to verify version before annotation that is correct (using signature).

regards

Pavel Vlcek

Hi Pavel,


Thanks for sharing the details.

I have logged above stated issue as PDFNET-41341 in our issue tracking system. We will further look into the details of this problem and will keep you posted on the status of correction. Please be patient and spare us little time. We are sorry for this inconvenience.