从/xl/worksheets/sheet1.xml part coldfusion poi中删除记录合并单元格

I am creating an excel file with java poi library, it gets created but when I am opening the file excel pops a message saying "We found some problem with the content of file.Do you want us to try to recover as much as we can.If you trust the source of workbook."I am creating an excel file with java poi libra