On the right side, select the Open checkboxes for the file types that you want to open in the Protected View. Now, select the Open selected file types in Protected View radio button at the bottom.

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.

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 ...

Getting a DAT file open on your Windows machine can require one of a few different approaches — to be determined by the kind of data the DAT file contains.

How to open a .csv file in Excel Opening a .csv file is as easy as opening a .txt file, and usually, you won’t have to clean up the data before doing so because the save task inserts the delimiter.

Don't manually re-enter data you find on the Web. Open Excel and transfer the data directly into a worksheet.

A CSV (comma-separated values) file is a text file in which information is separated by commas. CSV files are most commonly encountered in spreadsheets and databases. You can use a CSV file to ...