You can open the software with Notepad, which is shown, or you can open with another program such as Visual Studio, Excel or Notepad++. Click the program you want to use to open the file.

Simply put, .xlsx is a file extension for the open XML spreadsheet used by Microsoft Excel from 2007 onwards. Why the change in format from earlier versions of Excel?

Because Apache POI libraries are used in numerous open source projects, developing future libraries to support the Ecma Office Open XML File Formats (the default file format in the 2007 Microsoft Word ...