Report prompts for database login, although no database connection is set

Hey,

I'm using Visual Studio 2010, as well as Crystal Reports for .NET Framework (v13.0.12.1494).

I'm working on a tool, which collects data from a database and provides a list of objects to a report, to display this data. On my developer machine everything is working as expected, but when I want to run the tool on a test PC, a prompt pops up to enter database login credentials, once the report is opened. Since there is no database for the report to connect to, this prompt does not make any sense. The test PC has the runtime SP 12 installed.

This is where the report is created (the code-behind of a WPF window):

        privatereadonlyList<MeasureTestResult> m_MeasurementList;
        privatereadonlyMeasureLog m_ResultLog;
 
        privatevoid Window_Loaded(object sender, RoutedEventArgs e)
        {
            ReportDocument report = newReportDocument();
            report.Load("Sources/Report/ExportReport.rpt");
                        
            report.SetDataSource(m_MeasurementList);
            
            // wrap the result log object in an array, otherwise an error is thrown
            report.Subreports[0].SetDataSource(new[] { m_ResultLog });
 
            CrystalReportsViewer1.Owner = GetWindow(this);
            CrystalReportsViewer1.ViewerCore.ReportSource = report;
            CrystalReportsViewer1.ViewerCore.ToggleSidePanel = Constants.SidePanelKind.None;
        }

What can I do to get this to work?