Windows Media Player Won't Download Codecs Automatically? Here Is What Replaced It

Windows Media Player used to fetch missing codecs on its own. That switch was removed in Windows Media Player 12 and the server it called is gone, so here is how codecs actually reach the player now - and the two free installs that cover nearly every file.

If you are looking for the "Download codecs automatically" box in Windows Media Player and cannot find it, you are not missing it - it has not existed since Windows 7.

Windows Media Player 12, which is the version on Windows 7, 8, 10 and 11, has no automatic codec download at all, and Microsoft's old codec server has been switched off for years.

The good news is that the replacement is simpler: codecs now come from the Microsoft Store or from one codec pack, and both are free.

First, check which Windows Media Player you have

Windows 11 ships two different players under nearly the same name, and they get their codecs from different places.

• Media Player (the new app). The one pinned in the Start menu on Windows 11, with a dark modern interface - it uses only the Media Foundation codecs built into Windows plus the Store extensions.
• Windows Media Player Legacy. The classic version 12 with the menu bar and the library tree - it uses the Windows decoders for MP4, MOV and MKV and falls back to DirectShow for AVI and older formats, which is where a codec pack comes in.

To find out which one is complaining, look at the error. The new app shows 0xc00d5212 or "This item was encoded in a format that's not supported"; the Legacy player shows a code starting C00D, most often C00D11B1 or C00D10D1 with "the required codec is not installed".

Why the automatic download disappeared

Windows Media Player 9, 10 and 11 had a checkbox under Tools, Options, Player called "Download codecs automatically", and it pulled missing decoders from a Microsoft codec server - mostly Windows Media Video and the early Microsoft MPEG-4 codecs.

Version 12 dropped the checkbox when it arrived with Windows 7 in 2009, because Windows itself had started shipping the common decoders, and the codec server was retired soon after. Anyone still on Windows XP or Vista with version 11 gets a download error for the same reason: there is nothing left to download from.

The old advice on this page - loosening the "Download unsigned ActiveX controls" setting in Internet Explorer - is no longer safe or useful, and Internet Explorer itself was retired in 2022. Do not do it.

Fix 1: Install the free codec extensions from the Store

This is the modern equivalent of the automatic download. Windows already decodes H.264, MPEG-4, WMV, VP8, VP9, MP3, AAC, FLAC and WMA; the formats it leaves out are supplied as small Store apps that both players pick up as soon as they are installed.

• Install the Media Foundation Codecs bundle, which packages every Microsoft extension - HEVC, AV1, VP9, MPEG-2, Web Media and the HEIF, WebP and RAW image extensions - into one installer.
• If you only need H.265 for phone or camera footage, install the HEVC Video Extensions from Device Manufacturer - it is the free version of the listing the Store charges for.
• Close and reopen the player, then play the file again.

This covers MP4 and MOV files from phones, cameras and streaming downloads, which is most of what fails today. It does not cover AVI, Xvid, DivX or surround audio such as AC-3 and DTS - for those, keep reading.

Fix 2: Install one codec pack for everything else

Windows Media Player Legacy hands AVI files, DivX and Xvid video and most surround audio to DirectShow, and DirectShow can only use decoders that something has registered on the PC. That is the job the automatic download used to do, and a codec pack does it now.

• Uninstall any codec pack you already have, then restart - two packs at once is the most common cause of a player that used to work and does not any more.
• Install the K-Lite Codec Pack and accept the defaults; the Standard edition is enough for playback.
• Play the file in Windows Media Player Legacy - K-Lite's LAV Filters now decode Xvid, DivX, AC-3, DTS and the rest, and its Codec Tweak Tool can hand MKV and MP4 to them too if the Windows decoders keep failing.

Fix 3: Skip Windows Media Player for that file

If you only need the file to play and do not care which app opens it, VLC Media Player carries its own decoders for every format above and ignores what Windows has installed.

It is also the answer on a work PC where you cannot install codecs system-wide, and on a Windows N edition, which ships with no media components at all.

Errors you will see, and which fix they point to

Who should look elsewhere

If the file plays in VLC but every fix above fails in Windows Media Player, and the file is a purchased iTunes video or a download from a subscription service, the block is DRM rather than a codec, and no codec pack will change that.

If the codecs were working last week and stopped after an update or a pack install, the decoders are probably still there and only need re-registering - that is covered in How to Reinstall Default Codecs in Windows 11 and 10.

Quick questions

Nothing downloads itself any more, but one pack does what the old checkbox did and more.

Download the K-Lite Codec Pack and Windows Media Player picks up every decoder it was missing, or tell us which file finally played if you have been through this.