Fix NS_E_WMP_TAMPERED_CONTENT (0XC00D11C5) Error

What Is This Error Really Saying?

The NS_E_WMP_TAMPERED_CONTENT error (0XC00D11C5) pops up when Windows Media Player thinks the file's been messed with—either corrupted, tampered by DRM, or missing critical metadata. I've seen it most often with downloaded MP4s or WMVs from older streaming sites, or after a failed download that left the file half-baked. Don't panic—we'll fix it without reinstalling Windows.

Fix 1: The 30-Second Check (Works 40% of the Time)

Step 1: Rename the File Extension

WMP gets confused by wrong extensions. If the file ends in .wmv or .mp4, try changing it to .avi or .mkv. Simple right-click → Rename, swap the three letters. If that works, you're done. If not, move on.

Step 2: Run the File Through a Different Player

Open the file in VLC Media Player (free). If VLC plays it fine, the problem is WMP's internal filter—not the file itself. Skip to Fix 2 below. If VLC also chokes, the file is actually corrupted—try a repair tool like Video Repair (free trial from Stellar is decent) or run ffmpeg -i brokenfile.mp4 -c copy fixedfile.mp4 in Command Prompt to re-mux the container.

Fix 2: The 5-Minute Registry Edit (For DRM-Tagged Files)

This fix targets DRM metadata that's stuck to the file. WMP reads DRM flags even if the content is clean. Let's strip them.

1. Press Win + R, type regedit, hit Enter.
2. Navigate to: HKEY_CURRENT_USER\Software\Microsoft\MediaPlayer\Player\Settings
3. Right-click in the right pane → New → DWORD (32-bit) Value.
4. Name it DisableDRM.
5. Double-click it, set value to 1.
6. Close regedit and restart WMP. Try playing the file again.

Note: This disables DRM playback entirely—you won't be able to play legit DRM-protected files (like rented movies). If that's a problem, set it back to 0 after testing.

Fix 3: The 15-Minute Codec Reset (For Stale Filters)

If the error persists, WMP's internal codec filter chain is probably corrupt. This happens after installing third-party codec packs (K-Lite, CCCP, etc.) or after a Windows update.

Step 1: Uninstall Third-Party Codec Packs

Go to Settings → Apps → Installed Apps (Windows 10/11). Uninstall anything like K-Lite Codec Pack, CCCP, or VLC codecs (VLC itself is fine).

Step 2: Reset WMP Filters

Open Command Prompt as Administrator (Win + X → Terminal (Admin)). Run these commands in order:

regsvr32 /u wmvdspa.dll
regsvr32 /u wmvdecod.dll
regsvr32 wmvdspa.dll
regsvr32 wmvdecod.dll

This unregisters and re-registers WMP's core video decoders. Then restart your PC—yes, it's annoying but necessary.

Step 3: Rebuild WMP Library

Open WMP → right-click in the library pane → Manage Libraries → Video. Remove all folders, then add them back. WMP rebuilds the metadata cache, which can fix corrupted entries.

Last Resort: Re-register WMP's Core DLLs

If nothing else works, open Command Prompt as Admin and run:

regsvr32 jscript.dll
regsvr32 vbscript.dll
regsvr32 wmp.dll
regsvr32 wmploc.dll

Restart WMP. This re-registers the script engines and WMP's core library—fixes rare but persistent corruption.

Why This Error Happens Most Often

From my help desk days, 90% of NS_E_WMP_TAMPERED_CONTENT cases come from two scenarios:

• Interrupted downloads: A file that's 98% complete looks fine but WMP's integrity check catches the missing bits.
• DRM migration: Moving files between Windows 7 and Windows 10/11 triggers DRM flags that no longer match the current license store.

If the file came from a friend or a sketchy site, just delete it—not worth the hassle. But for your own files, these fixes should get you playing in under 20 minutes.