"Server has not yet been opened" using SQL Designer File

[PeteCozens]

I have an automated process which runs reports overnight, and exports them as Crystal Report files (this way, the data is saved with the report, therefore the client PCs do not need database connections).

When the report is loaded by the client app (written in VB6, using the Crystal 8.5 RDC Viewer), I get the error "Server has not yet been opened", but only for reports which are based on Crystal SQL Designer files. Any ideas why? The VB Code is as follows:

Dim objCrystal As New CRAXDRT.Application
Dim objReport As CRAXDRT.Report
Set objReport = objCrystal.OpenReport(strReportPath)

objReport.DisplayProgressDialog = False
objReport.EnableParameterPrompting = False

CRViewer1.ReportSource = objReport
CRViewer1.ViewReport

Thanks for any help,

Pete