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On 4/28/2014 2:21 PM, Aditya Panwar wrote:

Hi Team,

 

I have gone through the summary of this tool, actually we do have a requirement to encrypt “Digital signed PDF” file


Whoever wrote that requirement should read the specifications, because it is impossible to apply PDF encryption to a PDF that was digitally signed without breaking that signature!

A digital signature contains a signed hash of the bytes of a PDF. In some cases, you can append bytes to a signed file (incremental update), but that's not sufficient for your requirement: you want to encrypt the PDF. This means that you want to change the bytes of the already signed document. I'm sorry, but that will ALWAYS make the existing signature INVALID. (Actually: you don't need to read the specs to know this, common sense should be sufficient.)

in order to attain this functionality we required a tool, so can you please provide your confirmation on the same, would this tool able to meet our purpose or not.


You won't be able to encrypt a signed PDF with ANY tool as the requirement would be in violation with the specs regarding digital signatures.

Please contact sales if you require more information: http://itextpdf.com/sales/