Open" the csv file format into Excel from internet explorer 6

response.setContentType("application/vnd.ms-excel");
response.setHeader("Content-Disposition", "attachment;filename=" + fileFullName);

"C:Documents and SettingsUSERNAMELocal SettingsTemporary Internet
FilesContent.IE5QXJ0P436btbillsdfjlsfjk.csv' could not be found"