You don't necessarily need Microsoft Excel to work with an .xlsx file Reviewed by Ryan Perian This article explains what XLSX files are, how to open them, and which programs are able to convert ...

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 ...

How to edit .xlsx files on Mac So, how do you edit an .xlsx file on a Mac? Due to the open file format used by Microsoft’s Excel software, it’s surprisingly easy to edit a .xlsx file on a Mac.

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.

Upon opening an Excel file, if you see We found a problem with some content in filename.xlsx error, see this working fix.

Numbers has the ability to open Excel files so you can work on them. You can also export spreadsheets in Numbers so that they are compatible with Excel.