1 Reply Latest reply on Sep 18, 2013 1:10 AM by Steven Madwin

    Electronic Signature not saved when saving PDF to network folder


      Having an issue with PDFs that are saved to the server with an electronic signature.  After inserting the signature, the PDF is then saved to network.  While the file is still open, the signature is still visable.  Once the file is closed, and re-opened, the signature is no longer there.  I clicked in the spot where the signature should have been just to be certain that it's not invisible or that text color is white.


      If the file is created and saved locally, then copied to the network, the signature will appear.


      The PDF files are created from Excel files using the File, Save As PDF option.


      The enduser states that it was working until a few weeks ago. Not sure what changed.  If she was upgraded from X to XI.

      Also states that the options to add the signature were different (which leads me to believe that the version was upgraded).


      I tried creating a shortcut to the network folder on her desktop, then open the file from there, then save it.  This worked once but not again.  Doesn't sound like it would be a network issue.


      Windows 7

      Acrobat Pro XI.

      Novell Network


      Thanks in advance for any assistance you can provide.



        • 1. Re: Electronic Signature not saved when saving PDF to network folder
          Steven Madwin Adobe Employee

          Hi Kat,


          This is a bit geeky, but the signature appearance that you see on the page is not the signature, but just a graphical representation of the actual signature. The actual signature is a blob of hex encoded data in the PDF file that you don't really see. That aside...


          When you create a digital signature the first thing Acrobat/Reader will ask you to do is select a digital ID to sign with. Acrobat then reads the digital ID and amasses some information to use to create the signature appearance. It then fills in the form field (a signature field is just a special use form field) with the appearance, BUT the signature still hasn't been created. The next thing Acrobat does is asks you to Save the file to disk. This is more geekiness, but it much safer to compute the signature byte range on disk then it is in memory. The simple explanation is it's harder for the bad guys to manipulate the bytes on disk then it is for them to control the bytes in memory and because a digital signature provides document security we err on the safe side and require the file to be written to disk before the signature is created. The other safety item is, we want to sign the signature appearance so that someone can't come along later and modify the appearance without breaking the signature, so it (the appearance) has to be created before the signature proper is created.


          So at this point you've seen the signature appearance and thought that the signature has been created, but it hasn't. When you try to save to the network folder something is preventing Acrobat from saving the file and what ends up happening is the file is rolled back to the pre-signature state and the signature appearance is removed. The file is in essence untouched.


          All of that aside (which is probably more than you really wanted to know) the real question is why can't the file be saved to the network folder. This isn't really a digital signature issue, but rather a network permissions issue.