The easiest way would be to write an ADO query in VB that mimics your Crystal query with just a SELECT COUNT(*) FROM ... WHERE ...
If you get back 0 from the query, put up the message box and don't run the report. Brian J. Alves
Terrier Consulting, Inc.
Email: brian.alves@worldnet.att.net
VB / Crystal / SQLServer
(Currently available for consulting in Chicago)