Background; The Web application is developed for .Net framework 4.0. It has crystal report 9.2 integration. Application runs on Integrated Windows Authentication. The crystal reports are working fine when we execute, from solution running under Visual Studio 2010. When the same report are deployed to server (Web Server- OS: Windows Server 2003-SP2-32bit. DB Server- OS: Windows Server 2003-32bit) following error occurs, incorrect log on parameters. Crystal Report Runtime Engine for .net framework 4.0 has been installed in web server. Reports are configured to work on ODBC, System DSN with SQL Server driver. This drivers runs on SQL Server user account which has permission on database. There are no logon parameters passed from application. Just to verify, solution of passing the logon parameters from application is also tried, but the problem is not resolved.

Note: To resolve full access has been provided to IIS_WPG account on folder: C:WindowsTemp, C:WINDOWSMicrosoft.NETFrameworkv4.0.30319Temporary ASP.NET Files and web application. Server Error in /XXXX Application.

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Error in File E:WebAppsXXXXReportsCompanyStandard.rpt:
Unable to connect: incorrect log on parameters. 
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 

Exception Details: CrystalDecisions.CrystalReports.Engine.LogOnException: Error in File E:WebAppsXXXXReportsCompanyStandard.rpt:
Unable to connect: incorrect log on parameters.

Source Error: 
An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below. 

Stack Trace: 

[LogOnException: Error in File E:WebAppsXXXXReportsCompanyStandard.rpt:
Unable to connect: incorrect log on parameters.]
    . N(String  -, EngineExceptionErrorID  0) +582
    . I(Int16  !, Int32  ") +277
   CrystalDecisions.CrystalReports.Engine.FormatEngine.GetPage(PageRequestContext reqContext) +429
   CrystalDecisions.ReportSource.LocalReportSourceBase.GetPage(PageRequestContext pageReqContext) +172
   CrystalDecisions.Web.ReportAgent.|(Boolean  Z) +223
   CrystalDecisions.Web.CrystalReportViewer.OnPreRender(EventArgs e) +165
   System.Web.UI.Control.PreRenderRecursiveInternal() +103
   System.Web.UI.Control.PreRenderRecursiveInternal() +175
   System.Web.UI.Control.PreRenderRecursiveInternal() +175
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +2496