Access 97 and Access 2000 Report objects have an event called On No Data (check the property sheet for a report).
A simple way to handle reports with no data is to create a macro which, for instance, does the following:
1. Displays a message saying:
"No data exists for this report."
2. Issues a CancelEvent to stop the report opening.
Set this macro as the On No Data property for any report you want to do this for.
You can do more sophoisticated things if you are executing the report using code but this is the simplest.