I have xml as a datasource, 1.I am having one grouping in my report and my grouping field has values like 1,01,2,2,02,1,01,.... So I am grouping by this field and in sort option i m setting this field to get sorted on the field and it gives proper output. 2.In my report header i have to include one subreport since i want to print one iterated value in Report header band(adding virtual detail band by adding a subreport with detail band only in report header band) Due to my report requirement I have to use a sort option and subreport,but when i run the main report ,it shows the error "Error filling print :Error Evalauting expression Source text:((net.sf.jasperreports.engine.data.JRXmlDataSource) $P{REPORT_DATA_SOURCE}).dataSource("/node/dummyxpath")" When i run the same report by removing a fied in sort option it gives output...but when i have sorting and subreport it gives above error.. Please guide me...