Attaching PDF for Deisgn Binder

I am running SW2011, SP3.  I am trying to attach a PDF file to the design binder.  I have tried both at the assembly and the drawing level with no luck.  It gives me no error, but no file shows up in the tree.  I have not clicked "link" so it should show.  Was able to attach a Word document no problem, but the PDF file will not work.

Thanks in advance for any help.

Dan

SolidworksAssemblies