I wonder if those instructions were for an older version of Acrobat. In Acrobat X, "File, Edit, View, Window, Help" are the only menu items I see, as well. A lot of the stuff is now moved over into the Tools button at the far right. Tools> Protection> More Protection> Security Properties.
But an even easier way (while viewing the document) is to use Ctrl+D to open Document Properties. Then choose the Security tab. Mike
