How to batch unlock multiple PDFs which have same known password?

I have several PDF files each with the same password that I know.

What tool or method could batch unlock them and provide a copy of each of the PDFs as an unlocked version?

There's CutePDF - could I use this to print all the PDFs to PDF and it will batch unlock them?

Also: - Virtual Image Printer driver - sourceforge.net/projects/pdfcreator/‎ - pdfforge.org

Can these unlock in batch?

therobyouknow

Posted 2013-08-20T14:37:53.253

Reputation: 3 596

I don't have the reputation to post. In the terminal go to the directory with your files then call brew install qpdf then for file in *.pdf; do $(qpdf -password=password123 -decrypt --replace-input $file); done – Declan McKenna – 2020-01-23T15:33:25.283

possible duplicate of FOSS Script for unlocking PDF for printing

– Ƭᴇcʜιᴇ007 – 2013-08-20T14:56:28.780

I don't think that it is a duplicate @techie007 as that question deals with DRM, my question isn't about DRMed PDFs, simply PDFs that are password protected. Thanks. – therobyouknow – 2013-08-20T15:05:45.727

Password protecting a PDF is a form of DRM. ;) – Ƭᴇcʜιᴇ007 – 2013-08-20T15:47:46.687

Thanks techie007 - yes I agree there are many approaches to DRM which can include use of a password. But to me DRM is primarily about restricting how many copies of a file can be viewed, listened to or watched. I think my case is not primarily about DRM as here, a password is used on the PDF so that it is not seen by those who shouldn't but if it was made public there would be no such restriction. Also, I feel my answer adds value in the context of unlocking and in batch - the other answer may not occurred to others like me who are looking to just unlock a batch of files, not print them. – therobyouknow – 2013-08-20T16:00:03.250

I can see your points, and they are valid (or at least reasonable ;) ). Hence why it takes 5 votes to close -- we'll let others read what we've written here and they can decide. :) – Ƭᴇcʜιᴇ007 – 2013-08-20T16:03:24.370

Thanks techie007 :) Put it another way, if you wrote a book and sold it to me as a download password protected PDF and told me the password, then I could give copies to my friends and tell them the password so they wouldn't have to pay you money (which I wouldn't do because I'm a nice guy - I would make them buy their own from you). So This is not I would call DRM because it doesn't do what DRM is supposed to do. That's why amazon don't use it. Though I kno some publishers do do it but they also put the buyer's address on each page as a deterrent and to instill paranoia. – therobyouknow – 2013-08-20T16:12:09.900

On Linux you can use qpdf for the task. See here for a batch decryption script which can be easily integrated into the context menu of file managers like Nautilus.

– Glutanimate – 2013-09-08T18:02:29.250

+1 Thanks Glutanimate for the qpdf example, I did see qpdf in search results but the apparent fiddling with package managers etc put me off. Don't get me wrong, I use Linux all the time and deal with this stuff, I just didn't feel like the effort was worth it (maybe another time when I had more motivation perhaps). So the http://www.a-pdf.com/faq/how-to-decrypt-pdf-security.htm suited me just fine: download, install, run, clikc here and there and done! Life's too short... Oh, and I preferred a Windows solution as my tags in the question indicate. thanks anyway, upvoted ya!

– therobyouknow – 2013-09-08T18:42:00.603

+1 thanks I'll check it out when I get home and have time/access to the documents. – therobyouknow – 2013-08-20T15:04:50.753

1For me this didn't work, got error OWNER PASSWORD REQUIRED, but not given (or incorrect) when I tried BOTH user_pw and/or owner_pw as command line options as described in the documentation. Conclusion: pdftk didn't know how to decrypt my particular PDFs - but might work for someone else's. – therobyouknow – 2013-09-08T15:49:44.780

How to batch unlock multiple PDFs which have same known password?

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