Hi all,

I got following error when try to query a dataset in VS
Object reference not set to an instance of an object. Enesys.reportingservices.ersde2008

Below are the errors in Report server log when run the report:

w3wp!processing!1!7/2/2010-14:23:34:: w WARN: Data source 'DataSource1': Report processing has been aborted.
w3wp!processing!1!7/2/2010-14:23:34:: e ERROR: Throwing Microsoft.ReportingServices.ReportProcessing.ProcessingAbortedException: An error has occurred during report processing., ;
Info: Microsoft.ReportingServices.ReportProcessing.ProcessingAbortedException: An error has occurred during report processing. ---> System.NullReferenceException: Object reference not set to an instance of an object.
at Enesys.ReportingServices.Ersde.ErsdeDataReader.GetOrdinal(String fieldName)
at Microsoft.ReportingServices.DataExtensions.MappingDataReader..ctor(String dataSetName, IDataReader sourceReader, String[] aliases, String[] fieldNames)
at Microsoft.ReportingServices.ReportProcessing.ReportProcessing.RuntimeDataSetNode.RunDataSetQuery()
at Microsoft.ReportingServices.ReportProcessing.ReportProcessing.RuntimeReportDataSetNode.FirstPassInit()
at Microsoft.ReportingServices.ReportProcessing.ReportProcessing.RuntimeDataSetNode.FirstPassProcess(Boolean& closeConnWhenFinish)
at Microsoft.ReportingServices.ReportProcessing.ReportProcessing.RuntimeReportDataSetNode.Process()
at Microsoft.ReportingServices.ReportProcessing.ReportProcessing.RuntimeDataSetNode.ProcessConcurrent(Object threadSet)

The codes:
<?xml version="1.0" encoding="utf-8"?>
<root xmlns="http://enesyssoftware.com/schemas">
<queryName></queryName>
<description></description>
<list useDisplayName="true" title="list1"
relativeSiteUrl="/submissions/" tableName="list1">
<fields></fields>
<query>
<Where>
<Eq>
<FieldRef Name="User Region" />
<Value Type="Text">@Region!</Value>
<IfNot>All</IfNot>
</Eq>
</Where>
</query>
</list>
<resultSet>list1</resultSet>
</root>

The above codes works fine until I change to refer to another list say "list2". Any hints on what was the problem ? Thanks