1 / 8
Apr 2010

I've created a secure PDF with Mac's Preview program.

My intent is to require that a password be used only to OPEN file - there are no other restrictions placed on it, like read-only, for example.



I successfully uploaded file to e-junkie, entered appropriate PDF stamping code and password info.



When I 'purchase' and download this file, it is indeed stamped properly. But it is no longer encrypted and opens right up without any prompt for a password.



Please advise.



thanks!

~ Rick

Hi Rick,



You should be able to do this if you create a Master password for your file and a different Read-only password.



If your PDF has a Master password and a different Read-only password, use the Master password in the URL and your original Read-only password should be retained.

BTW, we do add a randomized Master password to every stamped copy of your file that we issue, so the file is encrypted under that password.



In practice, we have found that some files can retain their original, read-only password while others simply cannot, and we have found no clues to account for this difference between one file and another.



However, read-only passwords are pointless when you're giving out the password along with the file, as anyone who wants to share the file would include the password along with it, and it's not as if files "leak out" to the Internet without someone deliberately putting them there to share.



A read-only password that you reveal to anyone is only about as "secure" as putting a padlock on something and leaving the key in the lock, which is to say, it only provides the illusion of security without actually securing anything at all, so you really aren't giving anything up by losing that password.

Thanks for the reply.



Actually, I'm not trying to make my documents READ-ONLY. Rather, I prefer to require a password only to OPEN THE DOC. I have found that this is a reasonable (though not by any means fool-proof) security measure.



Is there a way to use PDF stamping while retaining this PW-TO-OPEN-DOC security?



I'm using Mac's Preview.



thanks!

~Rick

To clarify, when we say "read-only" we mean the password that will only let you read the document. This is the password that you are referring to that is required to open the document.

Two passwords can be set in a PDF file: the Master (author/editor) password which grants all access to do whatever you wish with the document, and the User/Open (read-only) password which only allows you to view the document along with whatever other permissions the author has granted in the file's security settings. I tried Googling for more info on PDF Passwords, but all I found were dozens of sites and programs all promising to disable/remove/crack PDF passwords. :^/



Have you tried uploading a file without any Master password and only an Open password (which you'd need to provide in the stamping URL)? The Stamper will add a randomized Master password anyway. Sometimes trying various password combinations will stumble into one that just happens to work for your particular file -- e.g., no Master at all, or same Master and Open password, or different Master and Open passwords, etc.



Although we tested the Stamper with a variety of files before offering it as a feature, in real-world practice since then, we have found that some files will retain their original Open password when stamped whereas others simply will not, and we have been unable to identify any clear reason nor even any clues to explain the difference. If we knew why the stamping or password retention failed whenever it does, or any specific difference between files that work vs. those that don't, then we could probably fix it, but we don't, so we can't.



Files created or modified with Mac Preview (or anything else using Mac OS X's built-in PDF libraries) seem more prevalent in reports that the original Open password was not retained in stamped copies or that the file could not be stamped at all; using Adobe Acrobat Pro to create/edit the original file seems most conducive for the best results, although we have received a few reports of problems with files reportedly saved in that program as well (though it's not clear if Acrobat was used to author the file originally or if any other program was involved in authoring or editing the file at any point).



Unlike our standard download process where every buyer receives an identical copy of your original file (passwords and all), the PDF Stamping process creates an entirely new file from scratch for each buyer, extracting only the content from the original file to use in each new, stamped file. This means none of the original file's security settings can simply be "carried over", since we're not merely modifying the original file. When the stamped file is created, any security settings must also be applied from scratch, which is why we provide for copy-paste and printing restrictions in the stamping URL.



Personally, if selling eBooks were my own livelihood, I'd be pleased just to get the Stamper working, and I wouldn't even have bothered with a read-only password in the first place, since that only degrades the customer experience for the buyer without any practical benefit whatsoever for me, the seller.

Thanks for this reply. A couple of comments:



1. I'm NOT trying to sell a read-only doc. I simply want to retain an open-doc pw.



2. Using Acrobat I've created master and user PWs. I've entered master PW in URL script place in product admin. I've tried uploading docs with different levels of permissions. Here are my results:



a. NO PERMISSIONS (other than full printing)... purchased doc retains Open/User PW, but does not show PDF stamp



b. SOME to ALL PERMISSIONS... purchased doc shows PDF stamp but does NOT require Open/User PW.



*

Any ideas?



Thanks!

~ Rick

In this discussion, "read-only" simply describes a PDF which has a User password that only allows the buyer to open and read/view the file. If you are trying to sell a doc which has such a User password, you are indeed "trying to sell a read-only doc". We're frankly not sure what else you could mean by "read-only", if that doesn't refer to a file that the buyer can only read and not modify in any way.



If a product is configured for PDF stamping but issues a download link that produces an unstamped file, that means the Stamper failed in its attempt to stamp the document, or maybe the Stamper was never invoked in the first place due to a bad Payment Variable Info URL, so we just issued an exact duplicate of your original file without any modifications whatsoever. This may mean your stamping URL is incorrect, or the file simply cannot be stamped due to its size (files larger than 20MB or so tend to have problems) or its security-encryption compatibility level was set too high (must be "Acrobat 5 or Higher" or earlier).



If the download link issued produces a stamped file, then whatever the Stamper did with that file is the best it could do with the original file it had to work with. If the original file's User password was not retained, that means the Stamper could not read that User password from the file to re-apply it to the stamped copies it created. Remember, the Stamper is not simply modifying your original file; it's creating an entirely new file for each buyer, where only the original content can be carried over, and not any of the original file's settings.



Have you tried uploading a file without any Master password nor other permissions and only a User password, with that User password specified in the Stamping URL? Also, remember to wait at least 15 minutes after you upload a new PDF, and use an actual test checkout to generate the download link (using "Send free download link" will not apply the Stamper).