Now that you are in the Default Programs window, click or tap 'Set your default programs'. Windows 7, Windows 8.1, programs, defaults, file extensions, protocols, Default Programs. If you’re on Windows 7, XP, or (bless your soul) Vista, you’ll need to burn the ISO to a USB thumb drive or DVD, or mount the ISO using a third-party virtual drive tool, like Magic ISO. In both Windows 7 and Windows 8.1, you can go to the Control Panel, click or tap Programs, and then Default Programs.
If you’re already running Windows 8 and you downloaded the RTM ISO from somewhere other than the Windows Store, you can install Windows 8.1 by mounting the downloaded ISO in Explorer by double-clicking it, and then running the installer. You should also ensure that you have plenty of free hard drive space (20GB+). Before you begin, you should consider backing up your important files and documents, but it’s not really necessary. Once you have the Windows 8.1 ISO on your hard drive, the installation process is painless. Bear in mind that if you go down this road, upgrading to a real version of Windows 8.1 will require a few more steps (discussed in the next section). It’s not as snappy as the final (RTM/GA) build, though, and has quite a few bugs/missing features. The other easier, and completely legal, option is to download the Windows 8.1 Preview from Microsoft. (But do make sure that you’re checking the right SHA-1 hash on the MSDN website your ISO might be mislabeled). If it doesn’t, assume the ISO has been compromised and download another. If you then use File Checksum Integrity Verifier (FCIV) on the ISO, the hash should match. If you hit up the MSDN Subscriber Downloads page, and then click Details under the version that you’ve obtained from elsewhere, you’ll find the SHA-1 hash.
While we’re not going to write a guide on how to obtain Windows 8.1 RTM from non-official sources, we will at least tell you to check the SHA-1 hash of the ISO that you download to make sure that it’s legitimate. If you don’t want to wait for October 17 or 18, there are two options for downloading Windows 8.1: You can obtain a copy (and a license key) from a friend/colleague with an MSDN, TechNet, or DreamSpark (student) subscription, or you can download a Windows 8.1 RTM ISO from your favorite file-sharing website (The Pirate Bay, Mega, etc.) To download and install Windows 8.1 for free, follow the guide below. If you’re using another operating system (Windows 7, Windows XP, OS X), you can either buy a boxed version ($120 for normal, $200 for Windows 8.1 Pro), or opt for one of the free methods listed below.
If you’re using Windows 8, upgrading to Windows 8.1 is both easy and free.
If you're running Windows 7 Home Basic or Windows 7 Starter, you can upgrade to Windows 7 Home Premium, Ultimate, or Enterprise to add full DVD capability or buy and install a compatible DVD movie player app.Windows 8.1 has been released. If you already have a player and are having problems with a codec, see Codecs: Frequently asked questions. Windows RT 8.1 doesn't support DVD movie playback. If you're running Windows 8.1 or Windows 8.1 Pro, you can search for a DVD player app in Microsoft Store.
Windows 8.1 and Windows 8.1 Pro don't come with DVD movie playback capability.
For more info, see Windows DVD Player Q&A. The Windows DVD Player enables Windows 10 PCs with an optical disc drive to play DVD movies (but not Blu-ray discs). If you have an edition of Windows that doesn't play DVDs and you want to play DVDs in Windows, go to Microsoft Store to buy Windows DVD Player or another app that plays DVDs.