I looked up what I did in an Access program to do something similar
using Acrobat 5. Later versions may be different. If this doesn't work,
I suggest searching the Adobe forums at www.adobeforums.com.

Add the registry key name PDFFileName to the "software\adobe\acrobat
pdfwriter\" key in the hkey_current_user hiererarchy. After each print
is completed, Acrobat should clear this entry and you will need to set
it before printing the next report.

Bill Simot