Extracting RAR and 7z files (including multi part archives)

Most builds arrive as archives: compressed files ending in .rar or .7z. Before you can write or install the build, you need to extract it (unpack it back into the real files). Big builds are split into many numbered parts, which looks scary but is easy once you know the trick.

What you need

• WinRAR from win-rar.com. This is our pick for RAR builds. It has a free trial, and it keeps working after the trial with a polite reminder.
• Or 7-Zip from 7-zip.org. Completely free and handles .7z perfectly. Recent versions open modern RAR archives too. If 7-Zip ever throws an error on a RAR build, try WinRAR before assuming the files are bad.
• Free space. Lots of it. More on that below.

The tool built into Windows (Extract All) is fine for ordinary zip files, but do not rely on it for split RAR builds.

Understanding multi part archives

A 200GB build is not uploaded as one file. It is cut into numbered pieces, for example:

• MyBuild.part01.rar, MyBuild.part02.rar, MyBuild.part03.rar and so on
• or older style: MyBuild.rar, MyBuild.r00, MyBuild.r01
• or for 7z: MyBuild.7z.001, MyBuild.7z.002

The pieces only work together. You must have every part, in the same folder, with the original names. You never extract each part separately: you open the first one and the program reads the rest automatically.

Step by step with WinRAR

1. Install WinRAR and restart your file explorer if the menu does not appear.
2. Put all the parts into one folder. Check the numbers run from first to last with none missing.
3. Right click the first part (part1 or part01, or the plain .rar in the old style).
4. Choose Extract files… (on Windows 11 it may be under Show more options, or in the WinRAR entry of the new menu).
5. In the destination box, pick a folder on a drive with enough space (see below), then click OK.
6. Wait. WinRAR works through every part in order. Big builds can take a good while, and that is normal.

Step by step with 7-Zip

1. Install 7-Zip.
2. Put all the parts into one folder.
3. Right click the first part (.7z.001 or part1.rar) and choose 7-Zip > Extract files…
4. Choose your destination and click OK.

Extract to a drive with enough space

This is the number one reason extractions fail part way through.

• You need room for the archives and the extracted build at the same time. As a rule, have at least as much free space as the total size of the parts, and a bit extra.
• Extract to a different drive from where the parts are if you can. It is faster and spreads the load.
• If the build contains one huge file (like a 200GB .img), do not extract it to a USB stick or drive formatted as FAT32. FAT32 cannot hold any single file over 4GB, and the extraction will fail. Use an NTFS or exFAT drive.
• Do not extract straight onto the SD card or SSD you plan to write the build to. Extract to your computer first, then write the image. See writing to an SD card.

Passwords

Most builds do not have a password. If yours asks for one, the build’s post will say what it is. Check the post carefully before asking.

What you end up with

• A single .img file: an image you write to an SD card, SSD or USB stick. See SD card, SSD or hard drive, or USB stick.
• A folder of files: usually a Windows front end that you copy and run. See installing PC builds.

Once it has extracted and you have checked it works, you can delete the archive parts to get your space back. (If you downloaded by torrent, you will stop seeding when you delete them.)

Downloaded by Usenet? NZB Grab, SABnzbd and NZBGet usually unpack the archives for you, so you may already have the finished files.

Still stuck? Errors like CRC or “unexpected end of archive” are covered in extraction errors. Antivirus jumping in? See antivirus false positives. Or ask in our Discord.