The file %s has reached its maximum size. To reduce the amount of data in this file, select some items that you no longer ...

The file %s has reached its maximum size. To reduce the amount of data in this file, select some items that you no longer need, and then permanently delete them by pressing SHIFT+DELETE. You could also consider using the new Outlook Personal Folders file (.pst) introduced with Outlook 2003 that provides greater capacity for storing items and folders.