Often subreports are used in Crystal Reports to retrieve an unrelated value from a different table or data source. In many of these cases you do not want to see the subreport at all. You just want to retrieve your value and use it. You soon realize, however, that if you suppress the subreport object, or if you suppress the section that contains the subreport, the subreport will simply not run.
To make a subreport run but be completely invisible you follow three steps:
1) Suppress all of the sections inside the subreport. This makes the subreport completely invisible, but still allows it to run. Do NOT hide or suppress the section in the main report that contains the subreport.
2) In the main report go into the menu using (Format > Subreport > Subreport Tab) and tick the property “Suppress blank subreport”.
3) In the main report go into the Section Expert and find the section that contains the subreport. Tick the property “Suppress Blank Section”.
This combination will make the section invisible, but the subreport will still run.
If you are using a really old version of Crystal you might not have some of these properties. There are some workarounds for these in the Crystal Reports “Expert Techniques” guides in my library.