How to change the default program a file opens with in Windows 7 When you open files that have a particular file extension, Windows will look at its configuration to determine what the default ...

This will cause Windows to open the Folder Options dialog box. If you look at Figure 1, you can see that at the very top of the dialog box, there is an Open File Explorer to drop down box.

Going through the same menu for every file is a waste of your time, so instead set up Firefox to download RAR files to the same folder every time without asking.