We have an Excel 2003 workbook, automated with VSTO, on a shared network
drive. The workbook contains pivot tables that refresh from live database
data when the user clicks a button. It takes about 10 minutes to refresh all
the data.

The 30 or so users who will look at the pivot tables each day have read-only
access. We have an administrator who has read/write access and performs daily
maintenance tasks.

We would like to implement an automatic process that will update the
workbook about twice a day at specified times. How should we go about
accomplishing this?