As obvious as it may sound, you need 7-Zip installed on your PC to follow this tutorial, so now is a good moment to do so, just click the big blue “Download” button above and start downloading the installer, once it is allocated in your hard drive, launch it, the InstallIQTM manager will guide you through the setup process.
So, turning 7-Zip into your default file archiver only takes a couple of steps and can be done in 2 different ways. The first way is through 7-Zip's interface. Open 7-Zip and go to Tools → Options...
The Options dialog will popup and there you'll find several tabs with parameters and different options.
Let's focus on the first tab: “System”, here you can see a full list of the file types 7-Zip can handle. Check those boxes you want 7-Zip to handle by default or if you want you can click on the “Select all” button to full selection.
Now click OK and the next time you'll open one of these files 7-Zip will launch.
The second way is through Windows Explorer, launch it and browse for one archive file of the type you want 7-Zip to handle and right-click on it.
From the popup context menu select Open with → Choose default program... and from the options available select 7-Zip File Manager.
As you can see in the next screen capture, the file icon changed to 7-Zip's indicating that from now on it will be opened with it by default.
Now you can have this extremely handy free file archiver to manage all your compression and decompression needs, and let me tell you that you'll never regret because besides being free and lightweight, 7-Zip is really solid and extremely effective. Download 7-Zip now by clicking on the “Download Now” link below, it's 100% free and no registration is required to download and install.