PDFs Requiring Password to Open When That Option is NOT Configured

[Pariah Burke]

TSPAM:

Problem: PDFs that were created WITHOUT a password required to open are asking for passwords before they will open.

Expected Result: PDFs should open without asking for an open password unless they were configured to require a password to open.

Analysis: PDFs were created via export from InDesign CS6 to PDF Version 1.7 (Adobre PDF Library 10.0.1). Document restrictions were defined as, Allowed: Printing, Content Copying for Accessibility, Commenting, Filling in Form Fields, Signing, Creation of Template Pages; other abilities Not Allowed. Restrictions use password security. Require a password to open is NOT set active.

Once posted online, several users report that the PDFs are requiring a password to open.

I can't duplicate that behavior--meaning that I'm never prompted for an open password--in Acrobat X or XI on Windows 7x64 or Mac OS 10.8x or in Chrome, Firefox, Internet Explorer, or Safari on those systems.

The PDFs in question are linked from this page: http://iampariah.com/blog/creative-pro/cs6-keyboard-shortcut-cheatsheets.php

[try67]

You need to get more full details from the users with the problems, such as:

- Double-checking that they requested to enter the password when the file

was opened.

- Application(s) used to open the file.

- OS used

[Pariah Burke]

I'm working on getting that information, but you know how people are when they're "Adobe doesn't work."

In the meantime I'm hoping others here can verify either the expected behavior or the problem.

[try67]

I opened the Photoshop file in Acrobat and Reader XI and it opened just

fine.

[Test Screen Name]

Background info: these files do not have a password but they are encrypted (because you set some security options). One of the characteristics of an encrypted file is that if the file is mangled/damaged, then it will look as if it needs a password.

[George_Johnson]

The encryption used means it can only be opened by Reader/Acrobat versions 10 or higher. There's really no reason to use this level for this document, so I'd suggest using something less.

[try67]

Well spotted. That's more than likely the problem...

[Steve Werner]

Customers could also be using non-Adobe PDF readers. Since you can't control this, all you can do is provide a suggestion to download the free Adobe Reader for best results.

[Pariah Burke]

Thanks, George. When did Acrobat/Reader change from warning users that the later-version PDF might have features that won't display to asking for a password?

Once upon a time one could rely that any modern version (from BAT/Reader 5.x up) would at least open the PDF even if certain features failed to work or the reader was giving a warning that the file was created with a newer version.

[George_Johnson]

I suspect they're using a non-Adobe PDF viewer, as Steve mentioned. Have you been able to confirm what they're using?

[Pariah Burke]

Reader 9 in the case of one person who tested for me.

[Steven_Madwin]

Hi Pariah,

There are two things here, 1) what is the version of the unencrypted PDF, and 2) how was the file encrypted.

The "may not display correctly" message occurs when the version of the PDF file is greater than what the PDF viewer (for us that's either Acrobat or Reader) understands. As an example, when Acrobat 1.0 came out 20 years ago it only understood PDF version 1.0. When Acrobat 2.0 was released it understood PDF version 1.1 and earlier. By Acrobat 8 it understood PDF version 1.7. If you had a PDF file that was version 1.7 and you opened it in Acrobat 7 (which I'm sure you've figured out only understands PDF v 1.6) then you'd get the "may not display correctly" message. Acrobat 7 would do its best to render the PDF, but if it came across something it just didn't understand it wouldn't (couldn't) display it.

Encryption is a bit different. Let's say you encrypt a file using Acrobat 10 and use the AES 256-bit encryption algorithm. If someone where to try and open the file in version 8, which only understands AES 128-bit encryption the the file could never be opened.

Finally there is the issue about how the password is saved. Acrobat 10 and later use a different methods of Unicode normalization and canonicalization then previous version, so if you've save a password using the Acrobat 10 or later settings then earlier versions cannot properly check that the password you've typed in matches what the document author set. I know this message thread started with the notion that there is no Document Open password, but it's not quite that simple. There really is a password, its just set to "NULL". However, Acrobat (and Reader) versions 9 and earlier cannot reconcile "NULL" set in 10 as they would "NULL" set in 9 and before. Thus, when the file tries to open in an earlier version you get prompted to reenter the password.

Steve

[Pariah Burke]

Worse.

When exporting Interactive PDF from InDesign CS6 or CC the ONLY PDF version that results is 1.7.

Yes, I can save down within Acrobat XI Pro, but that's not the point. Many, many publications are created as interactive PDFs exported from InDesign, and most of those carry some type of security. Now no one without Reader 10 or later can open those PDFs?!

Oh boy.

I'm bringing this to the Acrobat and InDesign product managers.

[Pariah Burke]

I've just uploaded new versions saved back to Acrobat 7 compatibility (the lowest I can go in BAT XI while preventing copying of the PDF content). Would you mind testing those, too?

[LC_2013]

I'm having problems with a small number of my PDFs. When I saved to view the problematic PDFs, either Firefox or Adobe seem to have changed my PDF security settings to:

Can be opened by: Adobe Acrobat 3 and onwards

Increases the PDF file size

Disables Fast web view

from:

Can be opened by: Adobe Acrobat 5 and onwards

Enabled Fast web view

[Test Screen Name]

How are you saving these PDF files, exactly, and what are you doing before saving?

Supplementary question: if you open the original file in Adobe Reader and close, is there a prompt to save?

[LC_2013]

In the prompt box asking to enter a password to open PDF, I click 'cancel'. I then click 'open with different viewer' in the top right (Firefox 22.0) which gives me the option to save or open.

If I open the file in Adobe Reader and close, I am not prompted to save.