Sub reports do not return data if there is no record in the main report.
In order to evaluate a sub report, you need to have at least one database record included in the main report. If there is no record in the main report, then the sub report will be considered as an on-demand sub report. When you double click the empty sub report, then the sub report will be evaluated and the data will be displayed. This is by design.
1. Open your report and go to main report Design view.
2. Add a database field with some data into any of the sections.
sub report will not return data if there is no record in the main report , 1186478 , KBA , BI-RA-CR , Crystal Reports designer or BusinessViews Manager , Bug Filed