4 Replies Latest reply on Nov 7, 2017 1:21 AM by Mauro Giovetti

    Document Signing Problem


      Hello, I can not sign my documents from my post. An automatic update was made by Adobe this morning, and since the following message appears, "the signature device does not take the SHA256 hash algorithm required. Would you continue to use the obsolete SHA1 algorithm or cancel the Signature? "  The signature device works properly on my colleague's workstation.

        • 1. Re: Document Signing Problem
          cadbury Adobe Employee

          Dear paulinel45647626,


          Thank you for reporting the issue.

          We have introduced this change in Acrobat functionality and it is expected to warn you when you try to sign with SHA1 hash algorithm.

          We have introduced this change as SHA1 has been royally broken and hash collision has been found. It is not safe to use SHA1 for signing any more. You can find the details of the issue if you click on Help in the warning dialogue.

          Here's the link for you   Applying a digital signature using the deprecated SHA1 algorithm warning message

          That is why we advise our users to move to SHA256 hash algorithm. But your device does not support SHA256.

          If you really want to continue signing with SHA1 you can go ahead with Continue in the warning dialogue and the functionality would remain the same for you.

          Please let me know incase you have any issue.


          Thanks and regards,

          • 2. Re: Document Signing Problem

            Hello, I have the same issue for Adobe XI (both Acrobat Pro and Reader). I tested in the same Windows 10, Smart card and smart card driver, Adobe DC can sign with SHA256, but Adobe XI can only sign with SHA1.


            I follow the   Applying a digital signature using the deprecated SHA1 algorithm warning message solutions but they are not worked for me. I also tested in Mac OS X, neither Adobe XI nor Adobe DC could sign with SHA256.


            My smart card can sign with SHA256 in other programs.


            Is there any idea for the issue?

            • 3. Re: Document Signing Problem
              paulinel45647625 Level 1


              My device support SHA 256 ! What's the problem?

              My coworker sign with SHA256 with the same device!

              I want to find the problem.

              Someone can help me??

              What's the problem?Certificat.JPG

              • 4. Re: Document Signing Problem
                Mauro Giovetti

                Buon giorno,

                anch'io mi trovo nella stessa situazione di paulinel45647625 e di tonyc947176.

                La versione di Acrobat Professional XI è la 11.0.22

                Sui PC con Windows 7 funziona tutto perfettamente, ma sui 2 PC con Windows 10 (gli unici con questo S.O.) si riesce a firmare nella sola modalità SHA1.

                Inoltre non vengono nemmeno visualizzate (quindi inserite) le informazioni della Firma in formato testo, è possibile inserire solamente la firma in formato grafico.