Fix NS_E_DRM_INVALID_KID (0XC00D2849) in Windows

Quick Answer

Delete the C:\ProgramData\Microsoft\PlayReady folder and reacquire the license for the protected file.

Why This Happens

This error pops up when Windows Media Player (or any app using PlayReady DRM) gets a file with a Key ID (KID) that doesn't match any license in your local store. The culprit is almost always a corrupted DRM cache — maybe from a failed license download, a system restore that borked the database, or switching user accounts. I've also seen it when someone renames a .wmv or .wma file after buying it, breaking the DRM binding. The file itself might be fine, but Windows can't map the KID to a valid license anymore.

It's not a hardware issue, and reinstalling Windows Media Player won't fix it. The real fix is nuking the local DRM store and starting fresh.

Fix Steps

Close all media apps. Kill Windows Media Player, Movies & TV, or any app that uses PlayReady DRM. Check Task Manager to be sure.
Delete the PlayReady folder. Open File Explorer and go to C:\ProgramData\Microsoft\PlayReady. If you can't see ProgramData, type it directly into the address bar or enable hidden items under View. Delete everything inside that folder — don't worry, Windows recreates it on the fly.
Clear the DRM license cache. Open an admin command prompt (Win+R, type cmd, press Ctrl+Shift+Enter). Run this:
```
del /s /q "%USERPROFILE%\AppData\Local\Microsoft\DRM\*.*"
```
This wipes the per-user license store as well.
Reacquire the license. Play the protected file again. Windows Media Player will prompt you to connect to the license server (usually the store you bought it from). Accept and let it download a fresh license.
Test playback. If the error's gone, you're good. If not, reboot and try step 3 again — sometimes the system locks files until a restart.

Alternative Fixes

If the main fix doesn't work, try these:

Run the Windows Media Player DRM reset tool — it's built into WMP. Open WMP, go to Tools > Options > Privacy tab, and click "Reset DRM Licenses". This does the same thing as the manual delete but through the UI. Won't fix it if the cache is locked.
Check file integrity. If the file came from an online store, download it fresh. Sometimes the KID in the file header gets corrupted during download. A fresh copy usually has a valid KID.
Disable third-party DRM software like AnyDVD or DVDFab temporarily. They can interfere with PlayReady license acquisition.
Try a different media player. VLC doesn't support PlayReady DRM, but if the file isn't DRM'd (some older files get mislabeled), VLC might play it fine. That tells you the issue is license-related, not file corruption.

Prevention Tip

Don't manually rename or move protected media files after downloading them. The license is tied to the original file path and filename in some cases (especially with older Windows Media DRM). If you must reorganize, copy the file, not move it — then verify playback before deleting the original. Also, avoid third-party tools that claim to 'strip DRM' — they'll corrupt the license store and cause this exact error.

One more thing: if you're on Windows 11 22H2 or later, Microsoft deprecated PlayReady in some builds. Check your Windows version with winver. If you're on a newer build, the error might not be fixable — the content just won't play. In that case, your only option is to find a DRM-free version or use an older machine.