We got this question at Tech Ed San Diego, so I'm posting the solution up:

Problem

A web application built using Crystal Reports for Visual Studio .NET 2002/2003.  The Report Viewer Control is used to display a crystal report.   A report using this DHTML Viewer displays data correctly on the first page, however the second page of the report displays the Report Viewer Control instead of data.

Solution

Set the Report Source in the Page_Init Event, not the Page_Load Event.

The Report Viewer Control displays on the page instead of the data if the Report Source is not set in the Page_Init Event of the Web Form Viewer. When a Postback Event is executed back to the server, the Report Source must be set.

The following sample code demonstrates how to set the Report Source correctly in the Page_Init Event:

Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init

'CODEGEN: the Web Form Designer requires this method call

'Do not modify it using the code editor.

InitializeComponent()

crReportDocument = New ReportDocument

crReportDocument.Load("C:\Program Files\Microsoft Visual Studio .NET 2003\Crystal Reports\Samples\Reports\Feature Examples\Chart.rpt")

CrystalReportViewer1.ReportSource() = crReportDocument

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NOTE:

Postback occurs when the web server reprocesses the current viewer page because you sent new criteria. This occurs when you execute a click event from the Crystal web viewer's toolbar.
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