Server Error

[21128]

I get an error message below when i try to run the report.
Can anyone please guide me how do i fix it?
thanks.


Server Error in '/eSOMS Reports' Application.
------------------------------------------------------------

Missing prompting unit.
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: System.Runtime.InteropServices.COMException: Missing prompting unit.

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:


[COMException (0x80004005): Missing prompting unit.]
CrystalDecisions.ReportAppServer.Prompting.IPromptEngine.startPrompting(PromptingUnits units, CRPromptingInfoProvider infoProvider, PromptingOption option) +0
CrystalDecisions.ReportSource.EromReportSourceBase.DoParameterPrompting(PromptingRequestContext reqContext) +321
CrystalDecisions.CrystalReports.Engine.FormatEngine.DoParameterPrompting(PromptingRequestContext reqContext) +44
CrystalDecisions.ReportSource.LocalReportSourceBase.DoParameterPrompting(PromptingRequestContext reqContext) +140
CrystalDecisions.Web.ReportAgentBase.DoPrompting(PromptingHTMLRenderOption htmlOption) +121
CrystalDecisions.Web.CrystalReportViewer.OnPreRender(EventArgs e) +966
System.Web.UI.Control.PreRenderRecursiveInternal() +80
System.Web.UI.Control.PreRenderRecursiveInternal() +171
System.Web.UI.Control.PreRenderRecursiveInternal() +171
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +842