NS_E_DRM_GET_LICENSESTRING_ERROR 0xC00D273C: License storage broken

When this error actually shows up

You're playing a purchased WMV file or a protected audio track in Windows Media Player, or maybe using a media app that calls MFPlay. Suddenly playback stops and you get 0xC00D273C with the message "License storage is not working." This happens after a Windows update, a disk cleanup that nuked the DRM folder, or moving user profiles between PCs.

What's actually happening here

Windows Media DRM stores licenses in a hidden folder at %PROGRAMDATA%\Microsoft\MediaPlayer\DRM. Inside is a file called drmstore.hds — acts like a mini database of all your licenses. When that file gets corrupted, or when permissions on the folder get stripped (common after a permissions reset or account migration), the DRM subsystem can't read or write licenses. The error code 0xC00D273C means the license store failed to open or initialize.

Another common trigger: antivirus software that quarantines or deletes drmstore.hds because it looks suspicious. Some aggressive security suites flag any encrypted binary blob as malware. Then you're stuck.

The fix — rebuild the DRM store

You don't need to reinstall Windows Media Player or run any complex repair tool. The real fix is deleting the existing corrupted store and letting Windows create a fresh one. Here's how:

1. Stop any media apps — close Windows Media Player, Movie & TV app, or any app that might hold DRM files open. Even if you think it's closed, check Task Manager for background processes.
2. Delete the DRM folder contents — open C:\ProgramData\Microsoft\MediaPlayer\DRM. (Put that path in File Explorer's address bar.) Delete everything inside — drmstore.hds, any .tmp files, all of it. Don't delete the DRM folder itself, just what's inside. If it says "access denied", you need to take ownership — skip to step 2a.
3. 1. If you get permission errors — right-click the DRM folder, go to Properties > Security tab > Advanced > Change owner. Set owner to Administrators group. Check "Replace owner on subcontainers and objects". Apply, then try deleting again.
4. Kill the DRM service — open Command Prompt as admin (Win+X, Terminal Admin). Run net stop "Windows Media Player Network Sharing Service". This frees any locked files. Then delete the folder contents again if step 2 failed.
5. Restart and test — reboot your PC. Windows Media Player recreates the DRM folder with a fresh drmstore.hds on first launch. Play your protected file again. It should prompt you to re-acquire the license (you may need internet).

What to check if it still fails

If deleting the DRM folder doesn't work, the problem is likely outside the DRM store itself. Check these:

• User profile corruption — create a new local admin account and test playback there. If it works, your profile has deeper issues. Move your files over and ditch the old account.
• Antivirus interference — temporarily disable real-time protection (don't leave it off) and test. If the error goes away, add C:\ProgramData\Microsoft\MediaPlayer\ to your AV exclusion list.
• Windows Media Feature missing — go to Control Panel > Programs > Turn Windows features on or off. Make sure "Media Features" > "Windows Media Player" is checked. It's not there by default on some N editions of Windows.
• Group Policy blocking DRM — in pro/enterprise editions, check Local Group Policy Editor under Computer Configuration > Administrative Templates > Windows Components > Windows Media Player. If "Prevent DRM access" is enabled, that's your culprit — set it to Not Configured.

One more thing: if you're using a really old DRM-protected file from like 2005, the license server might be dead. Microsoft shut down several DRM servers for old formats. In that case, no fix will work — the file is literally unplayable on modern Windows. Nothing you can do except rip it or find an unprotected copy.