Remove password from password protected pdf file

First convert the file to postscript (ps) file with poppler:

pdftops [your_protected_pdf_document.pdf]

Now reconvert it to pdf with Adobe Distiller. There, password has been removed from the pdf file.

On Linux do this:

pdftops {your_protected_pdf_document.pdf}
pstopdf broken_protection_pdf_document.pdf 


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