


(It's a couple of lines below the first set of radio buttons.) Click OK.

If you don't see Organize, press Alt+T, release the Alt key, and press letter O. Click the down arrow next to Organize, and select Folder and search options.Double-click Computer or any folder icon.Check (tick) the File name extensions box.Double-click This PC or any folder icon.How do I make file extensions visible so that I can change them? If extensions are hidden, you can't do that, so you need a way to display file extensions. The standard way to do this is for the sender to change the extension to TXT, and the receiver to change it back to ZIP or REG or XLSM or whatever. But you may need to send us a file of a type that your mailer rejects, or we may need to send you one. You can right-click the file and select Properties » Details to see its full name, or look at the Type column in Explorer to find a description of the file type, such as Microsoft Excel Worksheet. Most Windows installations are pre-configured to hide the file extensions, so a file actually called MyModel.xlsx would appear in Explorer as MyModel. The file extension tells Windows what program to run when you double-click the file - for an XLSX file, that's Microsoft Excel. For example, a file called MyModel.xlsx has a file extension of XLSX. Nearly all files in Windows have a "file extension", usually three or four letters after a dot.
