See: http://www.nabble.com/Unable-to-open-Excel-2007-file-%28block--0---already-removed%29-td22669473.html#a22681523 java.io.IOException: block[ 0 ] already removed at org.apache.poi.poifs.storage.BlockListImpl.remove(BlockListImpl.java:97) at org.apache.poi.poifs.storage.BlockAllocationTableReader.fetchBlocks(BlockAllocationTableReader.java:190) at org.apache.poi.poifs.storage.BlockListImpl.fetchBlocks(BlockListImpl.java:130) at org.apache.poi.poifs.filesystem.POIFSFileSystem.processProperties(POIFSFileSystem.java:530) at org.apache.poi.poifs.filesystem.POIFSFileSystem.<init>(POIFSFileSystem.java:176) at org.apache.poi.hssf.usermodel.HSSFWorkbook.<init>(HSSFWorkbook.java:312) at org.apache.poi.hssf.usermodel.HSSFWorkbook.<init>(HSSFWorkbook.java:293) Sample file that triggers it available from http://sik.dk/var/storage/elinstallatoerregister.xls
Fixed in svn However, your sample file can't be opened by hssf, as it's an excel 5.0 (excel 95) file format, and hssf doesn't read ones that old