Try to convert all cells to String using cell.setCellType(Cell.CELL_TYPE_STRING);
NPE.xls (application/, 22.50 KB, created by Ghaleb on 2013-11-03 12:08:53 UTC
Creator: Ghaleb
Created: 2013-11-03 12:08:53 UTC
Size: 22.50 KB

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Attachments on bug 55668: 31003