If you change your mind and want to select archives individually, then click “Deselect all”. If you want to open all archive types supported by The Unarchiver then you can click the “Select all” button. If 7z isn’t already selected, then go ahead and check the box next to it so that you can automatically open 7-Zip archives with The Unarchiver. As you can see, there’s quite a few and among the first is the 7-Zip or 7z format. When you open The Unarchiver, you’ll see its preferences.
