Document signing using both XChange Viewer and Acrobat

[pwglp]

Versions:
* XChange Viewer 2.5 (Build 205.0) Aug 14, 2012 17:23:22
* Acrobat X Pro 10.1.3

We created a Word file with three signature fields and then used the Acrobat X Word plugin to create a PDF (Test Signature form.pdf). We next opened the PDF using Acrobat X Pro and created three signature fields.

We verified that the fields showed as signature fields in both XChange Viewer and Acrobat. (Test Signature form-fieldset.pdf)

Next we signed the signature field version of the PDF in the first signature field using Acrobat X and the Acrobat "Certify With Visible Signature" option. The signature reason was given as "Form fill in and digital signatures". The signature type is self-signed PKCS. (Test Signature form-fieldset-alt1.pdf)

Next we opened this certified PDF over to XChange Viewer and signed the second signature line using the Certificate From A File option and a Reason of Approving This Document. (Test Signature form-fieldset-alt2.pdf)

Back to Acrobat Pro now and re-open the now twice signed document. In every instance we find that at this point the original Acrobat signature is indicated as invalid because the document has been altered or corrupted since it was signed. For emphasis here - the only change since the original signing in Acrobat was the signing in XChange Viewer. (Capture.png)

Does the group have any experience or guidelines to help with a document passed for signing between users with XChange and users with Acrobat?

One more note - I ran a similar test, but first signed using XChange with a reason of Attest to the Accuracy, then I signed using Acrobat, and finally signed one more time using XChange with a reason of Approve. When I went back into Acrobat at the end the first two signatures were invalid. (Test Signature form-fieldset-testb-3.pdf)

Any thoughts or suggestions are appreciated.

[Stefan - PDF-XChange]

Hello pwglp,

Welcome to our forums, and thanks for the detailed first post!

Could you please try to sign the same document twice with adobe - and attach the result?
(I only have the free reader here and it does not allow me to sign any copy of your document.)

Best,
Stefan

[pwglp]

Good morning/afternoon

I have attached three files. The first two signed within Acrobat Pro X. The third a snip showing the validity of the signatures as judged by Acrobat.

Thanks.

[pwglp]

One more followup to my last post. The two files here are a PDF that I signed via XChange Viewer after the two Adobe signatures. The PNG is a snip showing that signing via XChange apparently corrupts the document in some way per Acrobat thus invalidating both of the Acrobat placed signatures.

[Ivan - Tracker Software]

The issue is fixed. The problem was because document is certified and only some changes are allowed. Unfortunately, the widget name (/NM) of Singature3 field was changed by PDF-XChange viewer, what invalidates the signatures.

P.S. I'm not complaining, but Adobe's change of /F value in the same widget did not invalidate the signatures

[pwglp]

Thank you Ivan for the explanation. When you say the issue is fixed does that mean there is a patch to XChange Viewer or is the a procedure that I should follow when signing?

I am a touch unclear on the fix. My thanks again for the help.

[Stefan - PDF-XChange]

Hello pwglp,

What Ivan had in mind is that he fixed the problem in the code at our end. The fix will be available for you in the next build of our Viewer. As we are fixing some other issues with the .msi installer packages - there should be a new build released very soon (probably before the end of this week) and the fix for this problem will also be included in this upcoming build.

Best,
Stefan