AA9.0 Pro - Reset ddl on file open?

Question

I have some old documents with a handy little toolbar at the top, part of which is a drop-down list of document sections. The user can choose a section from the ddl and click a button either to print the section or go to it.
In my old version of Acrobat, I could make this ddl reset to the default value when the user opens the PDF. (Very simply, it was in Documents> Set Page Action, where I could add a "reset form" action to Page Open.) This reset is necessary. I don't want the nav bar to contain the user's last selection when the document re-opens, I want the default text.
I cannot figure out how to accomplish this in 9.0. I can't seem to find any way to tie an action to a file-open or page-open event. The closest thing I can find in the Help file is about the Actions tab on the form field itself, which can't do the job I'm looking for.
Is there something simple I'm overlooking?

Answer 1

> (Very simply, it was in Documents> Set Page Action, where I could add a "reset form" action to Page Open.)
This was a very old version of Adobe Acrobat.
Use following in the actual version:
View > Navigation Panels > Pages
Select the page and open the Page Properties. Then activate the tab Actions.