If you cannot open an Excel file and see Excel cannot open the file because the file format or extension is not valid error, see this post.

Learn how to change the default file format for saves in Word, Excel, and PowerPoint, so that you do not need to change it every time.

How to Convert DAT to Text in Excel. DAT files are files with an extension that isn't associated with a specific application or program and can be almost any type of file including video, media or ...

How to Change a Notepad Document Into an MS Excel File. When you're creating spreadsheet documents to track employee IDs, forecast sales or compare products, you may want to prepare your data in ...

Google Sheets is known for its versatility, namely its compatibility with Excel files. Here's a guide on how to convert Excel files to Google Sheets.