pdf that is updated by an excel document each time it Is opened?

This is absolutely possible, but only for a PDF on the same machine as the excel file. The easiest way to do this, with as little scripting as possible, is to create a livecycle form and use the data view tab to connect it to excel file. You'll need to learn a little bit about using data sources in a LiveCycle form. And you'll need to create a named area on the spread sheet. This name is required by the driver that connects to the spreadsheet, so that it can reference a specific set of data in the spreadsheet.

It doesn't get much simpler that this.

so what exatly do you want to get updated? a dropdown list? Or do you want to get a specific entry out of the spread sheet?

Thom Parker
The source for PDF Scripting Info
[url=http://www.pdfScripting.com]pdfscripting.com[/url]

The Acrobat JavaScript Reference, Use it Early and Often
[url=http://www.adobe.com/devnet/acrobat/javascript.php]http://www.adobe.com/devnet/acrobat/javascript.php[/url]

Then most important JavaScript Development tool in Acrobat
[url=http://www.pdfscripting.com/public/34.cfm#JSIntro][b]The Console Window (Video tutorial)[/b][/url]
[url=http://www.acrobatusers.com/tutorials/2006/javascript_console][b]The Console Window(article)[/b][/url]