AV1 Codec 2.0.35.0

Windows 10 and 11 ship without an AV1 decoder, so AV1 files open as a black screen, a codec error, or nothing at all.

The AV1 Video Extension is Microsoft's own fix for that, it is free, and it is a small download.

One thing to know before you start: what you get is a Windows app package rather than a normal setup program, and that is where most people get stuck.

What the Extension Actually Changes

AV1 is the royalty-free video codec built by the Alliance for Open Media, whose members include Google, Netflix, Amazon, Apple and Microsoft. It compresses roughly 30 percent better than VP9 at the same visual quality, and it beats HEVC without the licence fees attached to that one.

Installing the extension teaches Media Foundation to decode AV1, which is the layer Windows itself uses. That fixes playback in Movies and TV, Windows Media Player, the Photos app and File Explorer thumbnails, all of which ask Windows to do the decoding for them.

It changes nothing for players that carry their own decoder, and most good ones do. If you only ever open video in VLC Media Player, you do not need this at all, because VLC has shipped the dav1d decoder since version 3.0.8.

Which File to Take

The download page lists six files, which is four more than most people need. Take the top one unless you have a specific reason not to.

How to Install an AppxBundle

The file you get is named something like Microsoft.AV1VideoExtension_2.0.30.0_neutral_~_8wekyb3d8bbwe.AppxBundle. The tilde and the long string of letters are normal - that is just how Microsoft names Store packages.

The easiest route is the Microsoft Store link on the download page. It opens the Store on the AV1 Video Extension listing, you press Get, and Windows handles the rest including future updates.

If you have already downloaded the AppxBundle instead, do this:

• Right-click the file, choose Open with, and pick App Installer. Press Install when the panel appears.
• If nothing happens or you get an error, press the Windows key, type PowerShell and open it.
• Type Add-AppxPackage -Path " then drag the downloaded file into the PowerShell window, type a closing quotation mark, and press Enter. Dragging the file saves you typing that filename by hand.
• Wait for the progress bar to finish and close PowerShell. There is no confirmation dialog and no restart.

The extension installs for the account you are signed in as, not for everyone on the PC. Other users on the same machine need to install it themselves.

If You See "Invalid Value for Registry"

This is the most common failure and it looks alarming, so it is worth saying plainly: nothing is wrong with the file, and nothing is wrong with your registry.

The error comes from App Installer, the small Windows component that handles app packages you open by double-clicking. When App Installer is damaged, missing or out of date, it refuses the package and reports that message with the file path above it.

If PowerShell also refuses, the machine is probably blocking sideloaded packages. Open Settings, go to System then For developers, and check that installing apps from outside the Store is allowed - on work and school laptops it usually is not, and that setting is administrator-controlled.

Two smaller causes worth ruling out. A download interrupted partway through will fail validation, so try the link again if the file size looks short. And if Windows opens the file with the wrong program, use the right-click Open with route rather than a plain double-click.

Checking It Worked

Open an AV1 file in Movies and TV. If it played before and nothing has changed, restart the app first - Media Foundation caches its list of decoders and does not always notice a new one straight away.

If the file plays in VLC but still not in Movies and TV, the package did not install cleanly. Remove it from Settings, Apps, and add it again.

Worth ruling out before you go further: plenty of files people assume are AV1 turn out to be HEVC, which needs a completely different extension. Open the file in MediaInfo and read the video format line, or run it through the Codec Finder.

Hardware Decoding, and Why 4K Still Stutters

Installing the extension makes AV1 play. It does not make it play smoothly on an old processor, because software decoding 4K AV1 is genuinely heavy work.

Hardware decoding hands that work to the graphics chip instead, and current Intel, AMD and NVIDIA graphics all do AV1 in silicon - Intel from 11th generation integrated graphics and Arc onward, NVIDIA from the RTX 30 series onward, AMD from the Radeon RX 6000 series onward.

To check it is working, play an AV1 video and open Task Manager. Under Performance then GPU, look for movement in the Video Decode row while the processor stays fairly idle.

If it is not moving, keep your graphics driver current and turn hardware acceleration on in your player. Our guide to which GPUs decode AV1 in hardware covers what supports what, and there is a separate walkthrough on tuning AV1 decoding per player.

AVIF Photos Come With It

The same package adds AVIF support, which is the still-image version of AV1 and produces sharper photographs at smaller sizes than JPEG. Once it is installed, File Explorer shows AVIF thumbnails and the Photos app opens the files without complaint.

You can test it on these sample AVIF files, or turn your own photos into the format with a free JPG to AVIF converter.

For the full picture there is our guide to viewing AVIF images on Windows. Photos from an iPhone are a different format again and need HEIF Image Extensions instead.

Who Should Look Elsewhere

If your version of Windows says N or KN in Settings, System, About, the media layer this extension plugs into was removed at the factory. Install Media Foundation Codecs first, or the AV1 extension has nothing to attach to.

If your PC is managed by an employer or a school, Store installs and sideloading are usually both blocked, and no amount of PowerShell gets round an administrator policy. Install a player that carries its own decoder instead.

If you use MPC-HC or PotPlayer, you are already covered for playback, and the extension only adds the Windows apps on top.

LAV Filters extends the same coverage to any DirectShow player. The K-Lite Codec Pack bundles a player and the decoders together if you would rather install one thing than several.

Where to Go From Here

For the longer walkthrough, including which apps need the extension and which never did, there is our full guide to playing AV1 on Windows 11. Browsers are a separate question, covered in the guide to enabling AV1 on YouTube.

To make AV1 files rather than just play them, FastFlix gives you a proper interface for it, and there are the commands for encoding AV1 with rav1e and FFmpeg if you prefer the command line.

If you are still weighing the two formats up against each other, we looked at whether HEVC is still worth it.

Quick questions

Browse the full video codecs collection for related downloads.

Download AV1 Video Extension 2.0.35.0 and see whether that file finally plays, or tell us how you got on if you have used it before.