While it is technically possible to open an Excel file in Notepad, this is not a good idea. Excel files are binary files that contain complex formatting and data structures. When you open an Excel ...

How to Open an XLS File in Excel. XLS files are Excel workbook files created in Excel 97 or Excel 2003. The 2007, 2010 and 2013 versions of the program use the XLSX format by default to save ...

Microsoft Excel has several features designed to help you recover unsaved versions of files and prevent data loss.

Click "File," "Open" and browse to your second Excel file. Double-click the file to open it. Repeat the steps for each new file you'd like to open in its own window.