As a result, you may see an error message if you try to open your CSV file in another application on your Mac without closing it in Word first. Microsoft Word locks the files it opens so other applications can't open them at the same time, eliminating the prospect of file corruption that could occur if more than one application tried to save the same file at the same time.These options have no effect on CSV's plain text. Don't apply type styles, sizes or other features.
Look in the Applications folder for this useful application.