If you want to install or reinstall Windows 8.1 and don’t have installation media, you can create it from this page. You’ll need to use a PC with a reliable Internet connection and either save the installation files to a USB flash drive or burn an ISO file to a DVD.

Before you begin, here are some things you’ll need:

• PC with an Internet connection. If you don’t have a reliable Internet connection, maybe you can go to a friend’s house, library, Internet café, or somewhere else with Internet.

• USB flash drive. Use a USB flash drive with at least 4 GB of available drive space. We recommend using a drive with nothing else on it.

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• DVD. This requires a DVD burner on or connected to the PC you’re using to create the media, and a DVD player on the PC where you want to install Windows 8.1. Use a DVD with at least 4 GB of space, and we recommend using a blank DVD.

Here are some things to check on the PC where you want to install Windows 8.1:

• 64-bit or 32-bit processor (CPU). You’ll need to download either the 64-bit or 32-bit version of Windows 8.1 that’s appropriate for your CPU. To check this on your current PC, go to PC info in PC settings or System in Control Panel, and look for System type.

• System requirements. See the system requirements before installing Windows 8.1. We also recommend that you visit your PC manufacturer’s website for info about updated drivers and hardware compatibility.

• Language in Windows. You’ll need to choose the same language when you install Windows 8.1. To see what language you’re currently using, go to Time and language in PC settings or Region in Control Panel.

• Edition of Windows. You should also choose the same edition of Windows. This might be Windows 8.1 or Windows 8.1 Pro. To check what edition you’re currently running, go to PC info in PC settings or System in Control Panel, and look for Windows edition.

When you’re ready, connect your USB flash drive or insert the DVD, tap or click Create media, and then follow the instructions.

Create media

To install Windows 8.1, do one of the following:

• Connect the USB flash drive to the PC where you want to install Windows 8.1, browse to it in File Explorer, and then open the setup.exe file. Follow the instructions in setup.

• Insert the DVD into your PC, and then restart (reboot) it. Follow the instructions in setup.

Source: Windows.microsoft.com