hyperlink won't work when document is protected

[Rigmarol]

I've created a form with fields for dates, numbers, text and checkboxes.
My users keep modifying the form so I have protected it. I've been asked to
add a hyperlink to the document referencing another document that needs to be
signed and turned in with this form.
My problem is that while the form is un-protected the hyperlink works fine.
But when I protect the document not only does the hyperlink no longer work
but you can't copy and past it into your browser either.

Any suggestions?