Hi
I'm a student and I'm working in Visual Studio .Net.
I have to build a web application (webforms and webservice) including 
Crystal Reports.
The purpose is to show the data from the My SQL Database in a structured 
way on a Report Viewer.
To start with this new material, I've tried a simple piece of code.
The code is correct, I get no errors during compilation.
The link with the database is also correct, cause I get no errors in 
design view, and I see dummy values for my table.
However, when I run the application, I get the following error:

------------------------------------------------------------------------
Exception Details: CrystalDecisions.CrystalReports.Engine.LogOnException: 
Logon failed.

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: Logon failed.]
   .K(String 
, EngineExceptionErrorID )
   .F(Int16 , Int32 )
   .E(Int16 
)
   CrystalDecisions.CrystalReports.Engine.FormatEngine.GetPage
(PageRequestContext reqContext)
   CrystalDecisions.ReportSource.LocalReportSourceBase.GetPage
(PageRequestContext pageReqContext)
   CrystalDecisions.Web.ReportAgent.v(Boolean `)
   CrystalDecisions.Web.CrystalReportViewer.OnPreRender(EventArgs e)
   System.Web.UI.Control.PreRenderRecursiveInternal() +62
   System.Web.UI.Control.PreRenderRecursiveInternal() +125
   System.Web.UI.Control.PreRenderRecursiveInternal() +125
   System.Web.UI.Page.ProcessRequestMain() +1470
-----------------------------------------------------------------------

Does anyone know how I can solve this?