Directly printing works - but viewer fails with an error

Question

Hey,
we are using: Crystal Reports 2011 and runtime for VS2010.
I open and print my reports via c#. The directly printing works fine. But the viewer don't works. It's really crazy, because directly printing and viewing are using the same methods for database login etc.
At preview a form with the crystalreportsviewer will be opened and the reportsource is being set. After that the viewer shows the progress box. After a short while the progress box disappears and the following error is shown:
Crystal Report Windows Forms Viewer
Die Abfragen zum Abrufen der für diesen Bericht erforderlichen Daten können nicht ermittelt werden.
Daten konnten nicht aus Datenbank abgerufen werden.
Fehler in der Datei CS_201001_u {5BF5FF1B-C662-4A1E-80CA-B4BEB0124295}.rpt:
Daten konnten nicht aus Datenbank abgerufen werden.
OK  
Translated in english:
Crystal Report Windows Forms Viewer
The queries to retrieve the required data for this report can not be determined.
Fehler in der Datei CS_201001_u {5BF5FF1B-C662-4A1E-80CA-B4BEB0124295}.rpt:
Data could not be retrieved from database.
OK  
But the database logon methods etc. are all the same as at directly printing. What could it be?
            this.crystalReportViewer.ShowPrintButton = false;
            this.crystalReportViewer.ReportSource = pMainCRWReport;
            this.crystalReportViewer.ShowProgressAnimation(this._DruckOptionen.ShowDruckstatus);
            if (pPreviewOptions.Zoomlevel == 1 || pPreviewOptions.Zoomlevel == 2 ||
                (pPreviewOptions.Zoomlevel >= 25 && pPreviewOptions.Zoomlevel <= 400))
                this.crystalReportViewer.Zoom(pPreviewOptions.Zoomlevel);
                            pMainCRWReport.PrintToPrinter(pReport.Druckoptionen.AnzahlKopien,
                                                          pReport.Druckoptionen.KopieSeitenSortiert,
                                                          pReport.Druckoptionen.StartPage,
                                                          pReport.Druckoptionen.EndPage);
pMainCRWReport is ReportDocument.

Answer 1

Yes, it looks like that. I don't use postbacks or sessions.
I have inserted the following code just before the ReportSource of the viewer will be set.
ReportDocument doc = (ReportDocument)pMainCRWReport;
foreach (Table table in doc.Database.Tables)
       MessageBox.Show(string.Format("{0}: {1}", table.Name, table.TestConnectivity().ToString()));
All TestConnectivity returning true!
CrystalDecisions.CrystalReports.Engine.InternalException: Daten konnten nicht aus Datenbank abgerufen werden.
Details:  Datenbankanbietercode: -243
Daten konnten nicht aus Datenbank abgerufen werden.
Fehler in der Datei CS_201001_u {870C483C-D947-4FEA-A1C6-1AD0DC4A2805}.rpt:
Daten konnten nicht aus Datenbank abgerufen werden.
Details:  Datenbankanbietercode: -243 ---> System.Runtime.InteropServices.COMException (0x800002D3): Daten konnten nicht aus Datenbank abgerufen werden.
Details:  Datenbankanbietercode: -243
Daten konnten nicht aus Datenbank abgerufen werden.
Fehler in der Datei CS_201001_u {870C483C-D947-4FEA-A1C6-1AD0DC4A2805}.rpt:
Daten konnten nicht aus Datenbank abgerufen werden.
Details:  Datenbankanbietercode: -243
   bei CrystalDecisions.ReportAppServer.Controllers.ReportSourceClass.GetPage(PageRequestContext pPageRequestContext)
   bei CrystalDecisions.ReportSource.EromReportSourceBase.GetPage(PageRequestContext pageReqContext)
   --- Ende der internen Ausnahmestapelüberwachung ---
   bei CrystalDecisions.Windows.Forms.ReportDocumentBase.GetPage(Int32 pageN)
   bei CrystalDecisions.Windows.Forms.DocumentControl.ShowNthPage(Int32 PageNumber)
   bei CrystalDecisions.Windows.Forms.DocumentControl.ShowFirstPage()
   bei CrystalDecisions.Windows.Forms.PageView.ShowFirstPageEx()/
OK  
The error -243 is an informix error:
Could not position within a table table-name.
The database server cannot set the file position to a particular row within the file that represents a table. Check the accompanying ISAM error code for more information. A hardware error might have occurred, or the table or index might have been corrupted (truncated). Unless the ISAM error code or an operating-system message points to another cause, run the oncheck utility (secheck with IBM Informix SE or tbcheck with IBM Informix OnLine) to check and repair table and index.
It seems to be that the viewer can't read the records with are locked within a transaction. I don't understand why the direct printing works. Is it possible to set the ISOLATION LEVEL for the report database connections?
I have tried this note but it don't works.