A client from Oxford sent me a restricted PDF file which he wanted to modify (to add notes and highlight some text). The document was encrypted with the owner’s password, but didn’t require any password to open and print it.

There are a few ways to remove edit restrictions from such files. I tried 3 different methods, with the last one proving the most successful.

• If the document allows printing, you can simply “print” it to another PDF file. In order to do that, choose “Microsoft Print to PDF” virtual printer in the print dialog. This removed all restrictions and allowed to add notes. However, the resulting document increased in size over 10 times due to text being turned into images. This also prevented highlighting the text. So only a partial success with this one…
• I own “A-PDF Restrictions Remover” software license. Normally, it can remove restrictions from such documents with no issues, however, in this particular case it was asking for the owner’s password in order to remove restrictions, so it was of no use at all. Not sure why it didn’t work on that file, possibly due to me using quite an old version of the software.
• This was the most successful approach. Open the file on a Mac with its built-in Preview application, then go to File > Export and save it as a new PDF file. The resulting file was almost the same size as the original, fully editable and with no restrictions whatsoever. Success!