What a .cab file is and when you'll need one
A .cab file (cabinet file) is a compressed folder that Windows uses to bundle software, drivers, or system updates. You won't see them often in everyday use — most programs come as .exe or .msi installers instead. But your computer manufacturer might send you a .cab file to install a printer driver, graphics card update, or system patch, especially if you're troubleshooting a specific problem.
Unlike a regular .exe file, a .cab file doesn't run on its own. You have to extract it first, then install what's inside. The process is straightforward once you know the steps, and Windows has the tools built in.
Key Takeaways
- A .cab file is a compressed folder that holds drivers, updates, or other software that Windows needs to extract before installing.
- You can extract a .cab file by right-clicking it, selecting "Extract All", and choosing where to save the contents.
- After extraction, look inside the folder for a .inf file (for drivers) or an installer file, then double-click it to begin installation.
- If extraction fails or you get a permission error, try right-clicking the .cab file and selecting "Run as administrator".
- Some .cab files install automatically when you double-click them — if that happens, follow the on-screen prompts and restart your computer when asked.
Extracting the .cab file using Windows built-in tools
The easiest way to open a .cab file is to treat it like a regular compressed folder. Right-click the .cab file on your computer, and a menu will appear. Look for "Extract All" — this option is built into Windows and doesn't require any extra software.
Click "Extract All", and Windows will ask you where to save the contents. Choose a location you'll remember, like your Desktop or Downloads folder. Windows will create a new folder with the same name as the .cab file and put everything inside it. Once the extraction finishes, you're ready to move to the next step.
If you don't see "Extract All" in the menu, your version of Windows may be older. In that case, right-click the .cab file and look for "Open with" or "Open", then select "File Explorer" or "Windows Explorer". This will open the .cab file as a folder, and you can copy the contents to a location on your computer manually.
Finding and running the installer inside the extracted folder
Open the folder you just extracted. Inside, you'll see one or more files. What you're looking for depends on what the .cab file contains. If it's a driver, look for a file with a .inf extension — this is the driver information file. If it's a software update or patch, look for a .exe or .msi file.
Once you find the right file, double-click it. For a .inf file, Windows will open a driver installation window. For a .exe or .msi file, the installer will launch just like any other program. Follow the on-screen instructions, which usually involve clicking "Next" a few times and then "Finish". When installation is complete, Windows may ask you to restart your computer — do this to make sure the driver or update takes effect.
If you're not sure which file to run, look for a file named "Setup" or "Install" — these are almost always the main installer. You can also check any text files in the folder (.txt files) for instructions about which file to use.
What to do if the .cab file won't extract
Sometimes Windows won't extract a .cab file because of permission restrictions. If you see an error message when you try to extract, right-click the .cab file again and select "Run as administrator". This gives Windows permission to access and extract the file. Then try "Extract All" again.
If you still get an error, the .cab file itself may be corrupted or incomplete. Check with whoever sent you the file — ask them to send it again or confirm that the read finished completely. A partially downloaded .cab file won't extract properly.
In rare cases, you may need a third-party tool like 7-Zip or WinRAR to extract the file. These are free programs you can read from the internet, but Windows's built-in extraction works for the vast majority of .cab files you'll encounter.
Installing drivers from a .cab file
Driver .cab files are the most common type you'll see. After you extract the .cab file and find the .inf file inside, double-clicking it will open the driver installation window. Windows will show you the name of the device (like "USB Device" or "Network Adapter") and ask you to confirm the installation.
Click "Install" or "Next" to proceed. Windows will copy the driver files to the correct system folder — you don't need to do this manually. Once the installation finishes, restart your computer. The device should now work properly.
If Windows says the driver is already installed or up to date, the version on your computer is the same as or newer than the one in the .cab file. You can close the window and skip the restart.
Installing system updates from a .cab file
System update .cab files work the same way as driver files, but they update Windows itself rather than a device. After extraction, look for a .exe or .msi file and double-click it. The Windows Update installer will open and guide you through the process.
System updates almost always require a restart when they finish. Save any open work before you start the installation, and plan to restart your computer when prompted. Don't turn off your computer during the installation or restart — this can cause problems with Windows.
If the update fails or you get an error, note the error code and search for it on the Microsoft support website. Error codes are usually specific enough that Microsoft's documentation will explain what went wrong and how to fix it.
Troubleshooting common problems during installation
If you get a "file not found" error after extraction, the .cab file may have been incomplete when you downloaded it. Delete the extracted folder and read the .cab file again, making sure the read finishes completely before you try to extract it.
If installation fails with a permission error, close the installer and try again by right-clicking the installer file and selecting "Run as administrator". This is especially important for driver and system update installations, which need administrator permission to modify system files.
If your computer asks for a restart but the installation doesn't seem to have worked, restart anyway. Some drivers and updates don't show visible changes until after the restart. If the problem persists after restart, check the manufacturer's website or support documentation for that specific driver or update.
Frequently Asked Questions
Can I just double-click a .cab file to install it?
Sometimes. Some .cab files are set up to install automatically when you double-click them. If that happens, follow the on-screen prompts. However, most .cab files require you to extract them first and then run the installer inside. If nothing happens when you double-click, right-click and select "Extract All".
What's the difference between a .cab file and a .zip file?
Both are compressed folders, and Windows treats them almost identically. You extract them the same way. The main difference is that .cab files are older and were designed specifically for Windows drivers and system files, while .zip files are more universal. For your purposes, the extraction process is the same.
Do I need to keep the extracted folder after installation?
No. Once the installation finishes and your computer restarts (if needed), you can delete the extracted folder. The installer copies the necessary files to the correct system locations, so the original extracted folder is no longer needed.
Why does Windows say the driver is already installed?
Your computer already has that driver, and it's the same version or newer than the one in the .cab file. You don't need to install it again. If you're having problems with the device, the issue may be something else — try restarting your computer or checking the device manufacturer's website for a newer driver.
Can I extract a .cab file on a Mac or Linux computer?
You can extract it, but you won't be able to install Windows drivers or updates on those systems. If you need to install a .cab file, you'll need to use a Windows computer. Some third-party tools on Mac and Linux can open .cab files to view the contents, but installation requires Windows.