For all that you add xmlbeans-2.3.0.jar and it is not working,you must use HSSFWorkbook instead of XSSFWorkbook after add jar.For instance;
Workbook workbook = new HSSFWorkbook();
Sheet listSheet = workbook.createSheet("Kisi Listesi");
int rowIndex = 0;
for (KayitParam kp : kayitList) {
Row row = listSheet.createRow(rowIndex++);
int cellIndex = 0;
row.createCell(cellIndex++).setCellValue(kp.getAd());
row.createCell(cellIndex++).setCellValue(kp.getSoyad());
row.createCell(cellIndex++).setCellValue(kp.getEposta());
row.createCell(cellIndex++).setCellValue(kp.getCinsiyet());
row.createCell(cellIndex++).setCellValue(kp.getDogumtarihi());
row.createCell(cellIndex++).setCellValue(kp.getTahsil());
}
try {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
workbook.write(baos);
AMedia amedia = new AMedia("Kisiler.xls", "xls",
"application/file", baos.toByteArray());
Filedownload.save(amedia);
baos.close();
} catch (Exception e) {
e.printStackTrace();
}