The way I got around this problem (I don't think this issue is fixable at this point):
I am also using iTextSharp in my program. So I wrote a method using iTextSharp to check if the PDF file is password protected first, using help from this thread: http://stackoverflow.com/questions/11298651/checking-if-pdf-is-password-protected-using-itextsharp#_=_
So now I am checking for the problem before I run into it. It's the only way I've found around this problem.
I am also using iTextSharp in my program. So I wrote a method using iTextSharp to check if the PDF file is password protected first, using help from this thread: http://stackoverflow.com/questions/11298651/checking-if-pdf-is-password-protected-using-itextsharp#_=_
So now I am checking for the problem before I run into it. It's the only way I've found around this problem.