After saving LiveCycle forms to PDF, I try restricting editing with a password, an error message comes up: "This document cannot be saved. Bad parameters" ???

I am using a MAC and creating pdf forms. I want to restrict editing by implementing a password. I go to tools/Protect/Restrict editing, I type a password in, click ok. A message comes up saying I should save before changes will be implemented. I try saving the pdf and an error message comes up: "This document cannot be saved. Bad parameters." What should I do?