If your Excel files are opening in Notepad on Windows PC, here's how you can reset the settings to make .xls, .xlsx, etc files open in Excel.

The following steps will help you check updates for Microsoft Office: Open any Microsoft Office application, Word, PowerPoint, Excel, etc. Go to “ File > Account.” ...

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 ...