on its official Download Center, which provides a 180-day trial ISO. Requirements for Installation To use the ISO once downloaded, you will typically need:

Click to begin burning the setup files to the USB drive. Option B: Burning the ISO to a Physical DVD

Although Microsoft officially ended support for Windows 8.1 in early 2023, there are still many valid reasons to revisit this operating system. You might be reviving an older PC, supporting legacy hardware that lacks drivers for Windows 10 or 11, or simply needing the classic Windows 8.1 environment for a virtual machine.

Under , click Select and browse to the downloaded Windows 8.1 ISO file.

Microsoft provides the download through a specific support page, usually titled . The process differs slightly depending on your current operating system.

Click the Select button, browse your directories, and load your downloaded Windows 8.1 ISO file.

Microsoft originally designed a Media Creation Tool for Windows 8.1, similar to the tools available for Windows 10 and 11. This tool would allow you to easily create a bootable USB drive or download an ISO file without needing a product key upfront.

Insert your USB flash drive into an available port. (Ensure any critical data on this drive is backed up, as this process erases all existing partitions).

: This can occur if you are trying to install the wrong edition of Windows 8.1 (for example, you have a key for Windows 8.1 Home but are trying to install Windows 8.1 Pro).

Click the link matching your processor architecture to initiate the download.