We've had this problem in the past and it keeps creeping up. We have an old version of Adobe Acrobat (4.0) that has always worked for us. Unfortunately a modification to our Network has caused this issue to resurface even with this older version.

Basically we need the PDFs to print to file without the dialog popping up. There was a registry setting that worked in the past but for the life of me I can't remember what it was.