Chances are the subreport is incorrectly linked to the main report.
Open the main report in design view.
Right-click the edge of the subreport control, and choose Properties.
On the Data tab, what is in LinkMasterFields and LinkChildFields?
Access will choose the subreport records based on matching these fields. If
the properties are set wrongly, no records will match, and so the subreport
won't show anything.

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Allen Browne - Microsoft MVP. Perth, Western Australia.
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>I have an Access 2000 report with several subreports which have their
> own queries. All of the subreports display when I preview or print the
[quoted text clipped - 7 lines]
> Thank you,
> Michelle
Michelle - 22 Jul 2005 23:47 GMT
Thank you for your reply,
Fortunately I have solved the issue - two of the sub reports were
pointing to the same query - i changed one of them to point to
something else and that seemed to force both sub reports to appear when
previewing & printing from the VB application (tho they are still not
showing in layout preview).
Thanks,
Michelle