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git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1647512 13f79535-47bb-0310-9956-ffa450edef68

src/ooxml/java/org/apache/poi/ss/usermodel/WorkbookFactory.java

@@ -105,6 +105,7 @@ public class WorkbookFactory {
             NPOIFSFileSystem fs = new NPOIFSFileSystem(file);
             return new HSSFWorkbook(fs.getRoot(), true);
         } catch(OfficeXmlFileException e) {
+            // opening as .xls failed => try opening as .xlsx
             OPCPackage pkg = OPCPackage.open(file);
             return new XSSFWorkbook(pkg);
         }